Hi
For two people camping, you would likely do best with a 16 foot canoe so there is adequate room for gear, your stability is good and room to be comfortable. At that size, you can handle decent waves and, with the right design, Grade two rapids are no problem even if loaded.
While I use a double paddle in some of my canoes (no correction strokes and allows me to keep up with tandems and allows my wife to take extended breaks) I prefer a single blade because the double blade drips a lot of water into the boat and the braces are more effective. I am more likely to use the double paddle if I'm using my splash cover.
Incidentally, an open canoe can be rolled -- both the whitewater solo boats and tandem boats. I have not tried rolling a loaded canoe but they are pretty tough to tip so it didn't seem worth while (probably just lazy on my part).
Kayak is nice solo and just takes a bit different packing system. For Grade two, I prefer sitting higher and being able to stand occasionally for better visibility -- the trade off is less stability due to higher center of gravity. If you are using a tandem kayak, it takes more skill to maneuver due to the increased length but, as long as it is only Grade two, not much problem. Just remember, if you wrap a canoe around a rock, you can likely get free fast enough that you won't be hurt -- same situation is a kayak is critical and the additional length of a tandem increases the risk.
best
don
: OK, please don't think this is blasphemy!! But I have started to do some soul
: searching and I not sure of the answer why I want a kayak over a double
: paddle canoe. Yes I have paddled both and I prefer a kayak but I am not
: sure if it is really best for my needs.

: My primary use is a day boat for paddling. It will be a mix of big lake and
: small streams. No open water paddling. If I had a kayak, I might take to
: the Ocean on vacation but it would be rare. We do have a big lake and big
: waves, but big is 3 to 4 foot and that is only in really nasty times when
: I wouldn't be out on the lake. (Unless it was to play in the big waves).
: It takes a lot of wind to create waves like that for us.

: I want to do some camping with my niece. So I need the to be able to haul
: some gear. This will take place on mostly flat water. Some of the rivers
: around us have shoals and maybe a couple of class 2 rapids. Not real white
: water where we would go.

: The advantages I see are that a canoe could be lighter (no decking) and
: probably a bit more convenient to camp out of. Quicker to build but that
: is really an issue. Kayak being a closed boat is nice because it keeps
: unwanted water and animals and insects out. It can be rolled and a canoe
: can not. Of course she will probably never learn but the first 180 degrees
: anyway. :-)

: I will build me a kayak regardless, Maybe her a canoe and me a kayak. But I
: am serious in asking what advantages the kayak has for someone who spend
: their time on flat water and does a little camping? Not stirring the pot
: either!