Laf - Been there & done that. Just beware: The border crossings are going to be nightmares. (Always are on American holidays...)

Montreal has some great biking trails. There's an IMax theatre in the Old Port. An Insectarium (linky). Lots of good bars & restaurants. Try smoked meat sandwiches, and poutine. (Or smoked meat poutine - Two birds with one stone!)

The hike up Mount Royal is fun. No camping though.

Just some suggestions...