Hi mrcallow. I used to visit Montreal every few months for courses and I stayed just outside of the city in Point Claire at the Quality Suites Hotel. It's located close to the Airport and 5 minutes from the train station (Dorval) right at Boulevard St. Jean and Autoroute Transcanadienne (or St.Jean Blvd., and the Trans Canada Highway). You can give them a call at (514) 426-5060 for more information.
I have a good friend that lives right in Montreal as well. I'll email him and find out what he can recommend for the downtown area. That way you could just walk everywhere.
Check out the old city for street and architecture photography. You can also look here: