I see different responses from different people. I’ll jump in.
Montreal is a great city for a week-end getaway. Lots of culture, great restaurants and food, nice museums, Mt. Royal, Old Montreal, nice festivals and a fantastic nightlife. I’d even rank it among the top five in North America, maybe even the top three! It’s a very fun city and it’s fairly cheap with the exchange rate. There’s lots to do there. It’s a bit run down now, probably because of the massive construction going on in the city, but it’s nothing really bad.
Toronto. I lived there in ’99 and I didn’t find it all that spectacular. It’s not THAT clean (well…compared to some U.S. cities -- i.e. Detroit -- it’s immaculate) and the people aren’t too friendly. There’s the CN tower, the Royal Ontario Museum (ROM), Skydome (by far the most impressive sports stadium I have ever seen), the Ontario Science Center, the Toronto Zoo, nice ethnic restaurants, etc. Nightlife is so-so and you’d expect a lot more going on in a city of that size (5 million), so I don’t know if it’s worth a vacation. I only go there (and quite often, actually), to visit my sister who goes to school there or to meet up with my father who goes there often for business.
Rockies. Beautiful and I recommend you visit them. You might want to go to Calgary (YYC). Calgary is a really nice, clean and affordable city that is only an hour away from the Rockies. You can stay there and rent a car or take a shuttle to Banff National Park or to Lake Louise (absolutely beautiful!!). It’s a lot cheaper than staying in Banff or Lake Louise itself. Not much really to see in Calgary itself.
Vancouver. Vancouver is a beautiful city and definitely worth a visit. It might be a bit expensive though. It’s quite lively and diverse and has a good nightlife. I think the people there are somewhat superficial though. There’s Stanley Park (really beautiful), the Vancouver Aquarium, Science World, Chinatown, Grouse Mountain (there’s a gondola that takes you up to the top and affords an absolutely spectacular view of the city and other attractions on top…totally worth it!), great restaurants, and other attractions that I can’t think of right now. Whitsler is about an hour north and Victor is a ferry ride away (Victoria is mostly a retirement community and it’s not really worth more than a day’s visit, if you ask me). And the climate in that area is pretty mild, so it won’t be as cold as the rest of the country.
I can’t comment on Halifax because I haven’t been there, but my father went and he loved it.
If I were you, I’d go to either Vancouver or the Rockies (Calgary). There, you’d get a taste of the natural beauty of the country and some urban experience at the same time.