I am an experienced and avid open boat paddler, lots of whitewater experience, years of tripping experience on rivers and lakes in the Northeast US and in the Arctic. I've been at it for 30 years or more. Many experiences that have taught me lessons. I am a big guy - 250 Lbs. I am 60 years old. For some unknown reason I find myself attracted to the idea of learning to paddle a kayak, doing some day and overnight paddling on northern lakes and maybe some saltwater touring as well. I will likely do some paddling for exercise as well. My wife may join me. I am considering buying a couple of solo Kayaks. I am used to high quality equipment. Should I do this? If yes, what should I look for as far as a decent kayak that will fit me. My wife is 5'6" 135 lbs. Medium level experience - all in open boats. I have paddled a C-1 but it was a long time ago and I did not like it. I was over 40 and the kneeling was killing me. But I did manage to develop a passable brace up type roll in the C1.
Fer God sake…Nooooo!!!
Gadzooks, dun't do it! Yer'll go straight ta Hell (or Joisey)! A diehard canooist stoop so low as ta go ta a 'yak... blastfeemoos ah' says! Have yer no shame?
Go lie down fer awhile... git yer mind right... watch some Bill Mason DVDs... git yer mind right.... have a couple o' beers... git yer mind right... go out back an' whisper sweet nuttin's (in French) ta yer canoo... git yer mind right... look lovin'ly at yer canoo.... git yer mind right... run yer hands down de sleek keel... git yer mind right...
In no time yer'll git yer mind right an' like havin' ett a bad batch o' 3 day old Chinese food dat feelin' o' wantin' a 'yak so shall pass!
Yer kin' be cured - ask Andy_S.
FE
A Couple Options
If you’ve got a shop close by see if they have a demo day or give lessons. Try to paddle a couple very different boats to see what works for you.
SYOTR
Randy
Demo, demo, demo
Second that!
Go demo some boats. But do take care not to waste your time on those big floating bathtub.
If you're going ocean touring, 16' is where you should start looking. Anything shorter than that will not be worth your time.
Also, ask to demo one that track well, and another that has lots of rockers. You can get a feel for the range of different kayak designs. (if the shop guy doesn't know what you're talking about? go to another shop)
Go see Umiak Outfitters in Stowe
They carry a lot of brands and are very knowledgeable and experienced.
You clearly need a kayak, but …
there is no reason to chose between canoe and kayak. Both work well for particular circumstances. I don’t paddle a canoe because of my knees and where I want to paddle. But don’t pay any attention to anyone who says you need to do only one (except in jest). Get yourself a really good sea kayak (also controversial here) and go for it. My biased, personal recommendation is a QCC 700X and an Onno wing paddle. Others may recommend an elf shoe Brit boat but pay them no attention.
I just did what you’re contemplating.
I’m about the same size as you and after demoing I bought a used P&H Capella 173, composite hull. With only canoe experience it was difficult to select the best kayak and I mainly chose on comfort.
Might benefit from some more specifics -
Demoing is an excellent suggestion but I think more useful for someone buying their second boat. Plus, I honestly don’t have the time to do too much bopping around looking at boats. Maybe one saturday at best. I’d like to get a few good make and model suggestions here (and yes check out Umiak) and then just spring for something. Down the road I might change to a different boat but right now I would have very little clue what to look for in a demo except as you say comfort. At a minimum some specific thought from you folks will give me some food for thought when I run up to Umiak.
What are two or three popular and generally available brands and models in the 16-18 foot range that would handle my size/weight well and be reasonably easy to sell? Being realistic, I’m not looking at carbon or anything that expensive at this point. Maybe a less expensive composite? Maybe plastic? My use will be flatwater - maybe some good solid chop but nothing hair raising. Do I look for lots or rocker, nice and straight, something in between? What about buying a decent used boat?
Well if you demand the best
Go with the QCC! Talk to Steve and decide between the 500 and 700. I’m 5’9" 210# and the 700 fits me well.
I’ve had the feeling I was at my limits in rough water but never reached the boats limits.
Good luck !
Randy
my choice
I’m not quite as big as you–210-- but I have similar experiences in open canoes to you, although I paddled a C-1 and C-2 for quite a few years. A couple of years ago my wife and I bought sea kayaks. Got Prijon SeaYaks. We like them. Readily available, relatively inexpensive (used around $300 I think), and if it doesn’t work out, pretty easy to sell. Got a Perception Sea Lion for our teenage daughter. I find the Prijons more comfortable that then Perception.
I’ll try…
I spotted this segment in your reply that might be easiest as a starting point. "What are two or three popular and generally available brands and models in the 16-18 foot range that would handle my size/weight well and be reasonably easy to sell?... Maybe a less expensive composite? Maybe plastic? My use will be flatwater - maybe some good solid chop but nothing hair raising. Do I look for lots or rocker, nice and straight, something in between? What about buying a decent used boat? "
First, your return on resale will always be better on a used kayak because the biggest drop happens from new. The things that will cause a boat to drop a bunch after that are condition and currency of the model. A boat that is a particularly old model that has been lapped by newer designs is going to return less than one that is more current. One strategy may be to see what comes up for sale used in profusion around you. If you see a lot of a particular kayak maker, this is probably one that sold new pretty easily and is popular around you.
There is not an exact science here - for ex there is only so far an NDK Romany ever drops because it is such a well regarded design for both babysitting new paddlers and being a learning platform for any skill you ever want. But most makers have lines like the Solstice series by Current Designs, once really dominant but now lapped by CD's newer designs with lower decks and a different performance ethic. Same with QCC - they have some older designs that they still make, but the market (and higher end performance) is in the newer ones.
So if you buy an older model line used, you should be paying much less for it. But keep in mind that what makes that model line more obsolete is often that it doesn't have performance that paddlers now want.
As to more or less rocker - this is the same as canoes. More rocker means more maneuverable and slower, less rocker trackier and usually faster. This also means that you have to take the trackier boat further over on edge to turn it unless you get a rudder and use that instead. You are talking about two paddlers here, so you may have two different comfort levels with being over on edge. You and your wife may take differing levels of rocker to stay in your comfort zone.
Solid chop of a couple of feet shouldn't bother a boat that is stiff, ie trackier, enough to make it difficult to throw around. Stuff bigger than that could.
Plastic is more easily abused without repair and heavier, composite is lighter and more repairable. Which is easier depends on how you like to spend your time and how you will be hauling the boats. Storing out of the sun makes both easier.
Your wife is a small paddler - she just about the target for something like the Tsunami 135, a fully equipped kayak with perimeter lines and two bulkheads or the Necky Eliza.
Kayaks tend to fit both by volume (weight) and height because of leg length. By 250 pounds shoe size may be a factor as well. You may have to sit in a few boats to see if they work, or give more of that info here to make sure you get advice from paddlers who match up to you.
Don’t buy new
Buy used.
You can sell them for what you bought them for! So you don't have to be as careful in selectinng the "right" baot. You get to "demo extensively" for a season before you choose to keep it or trade for something different!
Still, you want to narrow it down to certain characteristic by paddling a couple back to back. Pick a windy day, preferably with chop. You can easily seperate the "man from the boy" of different boat design!
Sorry I can't help with specific model. I weight only half your weight.
[EDIT]
In terms of tracking vs. rocker. You can have it both ways in just about ANY kayak. A boat with lots of rocker can be stiffen up by a skeg. Or a trackie boat can have the aid of rudder. So it really boils down to personal preferences. Try both kind and see what YOU prefer.
I strongly advise that you try some out
before you jump and buy a high end kayak that you might regret.
I paddle a QCC-700, and worked my way up to it.
Looking back there is no way I could have jumped in that boat when I first started kayaking.
At your weight, I think a QCC-500 might be a good choice, and the good thing about buying from QCC, is if you don’t like the boat, they will take it back the first month.
Jack L
"Others may recommend…"
a blunt boat akin to these shoes 
QCC makes very nice boats However, there are many good boats out there of an array of designs. Demo as many as possible. Talk to other paddlers who do the kind of paddling you are contemplating. Try their boats find what they recommend.
Buying used can be the best decision. That way if you change your mind, you can sell the boats for what you paid.
Your skills will transfer
I find open boats much tougher than kayaks. Your experience and skill in canoes will transfer to kayaks. Demo as much as possible and buy used.
"the best"
Be wary of those who insist they know ‘the best’ for you. There are many excellent boats.
Best for whom and what?
Second that.
Too many jump into a hobby buying the top of line equipment only to realize that, even though the equipment is good...for someone else, it doesn't suit them!
To the OP, think back to your canoe buying experience. At what point did you figure out what type of boat you REALLY like? And how did you arrive at that point? How many boats didn't you go through? And how many boats do you end up owning even now?
May not be so for OPer
This is someone with prior experience in canoes in less than easy conditions if I read right. We have found that these folks can often just jump right into a skinnier kayak with no problem, in fact it’s better for them because they don’t get bored.
We just went thru this with an acquaintance. He was thinking that he should start out with a shorter and fatter kayak, but we had already put him into the hairiest kayak we have on a pond and he loved it. So we steered him towards trying a Tempest 165 before he pulled the trigger on a QCC 4 or 500 that he’d found listed. He got it - loved the how the Tempest was more responsive and has been paddling it at every opportunity since he got it a couple of weeks ago with no problem. His alternate sports were racing canoes and motorcycles in his younger days.
Somewhere to start…
These days, when I recommend specific boat(s) to paddlers with whom I haven’t paddled, I usually suggest they demo Tempests. The Wilderness Systems Tempest series comes in 3 sizes and are widely available new or used and 2 of the sizes are available in either poly or composite. These boats are reassuring for paddlers new to kayaks, yet are very capable and supportive of advancing skills.
I have 4 sea kayaks and split my paddling time among 3 of them: Valley Aquanaut, NDK Romany, Valley Nordkapp LV. Though I personally enjoy all three, I do not recommend the Nordlow to folks new to sea kayaks. I think the Romany is an unsurpassed boat for novices, but the Tempest might be a better all round boat.
I say go for it
After being a long time flat and WW canoer, I just got tired of lugging the big things around. If you are planning on more open water and perhaps even sea kayaking, they are much more user friendly for paddling in wind and waves, and easier to load and launch imho.
A couple of things to consider for a boat for you…
First, you will not have nearly the options your wife will have. There are very limited choices in good boats for big guys, and by that I mean ones that fit comfortably. I am 6’3" and weigh about 250, and am not too much younger than you. If that sounds near your specs, then consider that you will have only a limited number of boats that you will feel comfortable in despite what people try to tell you who are no where near your size and age. Size matters very much in this business, and subtle differences are often not so subtle in reality. Those who weigh 220 seem to fit many more boats than us. There are boats they recommend for larger paddlers that I can’t even get in without a lot of effort, and then want to get out of it after a very short time because it is just too uncomfortable. I did my time in a close fit WW kayak, so prefer something a little better for touring these days.
There are also flexibility considerations getting in, and especially out, of the things easily, not to mention the seat and leg room comfort factor. Consider a kayak with a wider and longer cockpit, a higher deck for more leg room if you have larger legs, and a bit of a wider seat. It is easier to custom fit a kayak cockpit that is slightly too large than make one too small work. A younger person may enjoy a more snug fit, but it gets tiring fast and lessens your enjoyment if the boat does not fit when you are older. Smaller people seem to greatly underestimate the fit considerations for someone even slightly larger than they are.
That being said, the only boats that fit me well are the Eddyline Nighthawk 175 (or the discontinued Merlin XT), a few of the Tsunami models (145 and 175), and the Solstice GT Titan. Fortunately, they all perform pretty well.
Don’t let age be a hold back. Among my group, I have a dozen plus who are all avid seakayakers. We rarely do paddles less than 15 miles, often much more and most of it on open water, sometimes several miles off shore, and live for days with Beaufort force 4 conditions with at least decent 2+’ swells. The youngster in the group just turned 53. There are 5 over 60, and 3 of them are ladies. Most of us have been paddling together now for about 3 years. Only a few had much, if any, kayaking let alone seakayaking experience before. Find someone who knows what they are doing to paddle with, and I mean really knows what they are doing with a group, and go with them. I think you will find it very rewarding.