Hi Dan, I see William already pointed you to our site at
www.gokayaking.ca as well as his own website, but specifically given your request, a couple of best bets:
Put in the Rideau River at the old Hog's Back Marina on Mooney's Bay, and paddle south. The Rideau Canoe Club is on the other side, and lots of paddlers use those waters. Lots of parking, easy launch.
Put in the Rideau River where it is joined by the Jock River. You can go south a short distance to the locks and turn around or go north quite a distance before turning back, also look for Mosquito Creek on the east bank as a fun diversion. Lots of parking, easy launch.
Put in the Ottawa River at Shirley's Bay. The river is wide here so stay near shore if you are a beginner, this is only a good spot early or late in the season as boat traffic is pretty high the rest of the time. Easy launch, good parking.
Probably the very best place for a quiet paddle with parking, a short drive, a nice launch, and good scenery is Meech Lake. Very little boat traffic any time of year.
If a little bit of a drive is OK, then the Clyde River starting from Lanark or the Tay River starting from Perth are very nice paddles. The Tay features an incredible marsh.
Keenan