Depending on what type of fun you are into you could spend a couple of weeks in the Toronto area and never get bored. There is the Royal Ontario Museum, The Ontario Science Center, SkyDome, the CN Tower, Canada's Wonderland Amusement Park, The Toronto Zoo, Ontario Place, or Harbourfront Center for a little culture. Downtown Toronto has lots of great shopping etc and a huge mall called The Eaton Center.
There's lot's more big city stuff like the fashion district and stage shows etc... Oooh and let's not forget that Totzkeeeeee lives only an hour away from Toronto. :)
If you are more into nature than the big city stuff then there's no beating Western Canada. The Calgary Stampede starts next month. It's an all out Rodeo extravaganza. Calgary itself is a beautiful city with a lot to see and do. Less than 2 hours by car from Calgary is Banff National Park. From there you can head up to Lake Louise, and further north to Jasper. From Jasper you can head back eastward to Edmonton which is about 3 hours or so north of Calgary. There you will find the West Edmonton Mall. This is the biggest mall on the planet. It has an amusement park inside and just about everything else you can imagine. You could stay at the Fantasy Land Hotel where you and the Mrs. can get your freak on in one of the themed rooms while the kids are kept busy elsewhere.
There's some food for thought. Let me know if you need anything else and I'll be happy to help you out.
Happy trails!
Dave
Just because I can.