I am the man of architecture and history. If you like the same thing, Montreal is the place. You HAVE to visit the Notre Dame Cathedral, voted to be one of the best display in North America. You can sit for hours and hours, admiring the blue accented altar and statues.
Don't forget to visit the Place Jacques-Cartier. Here you can sit down drinking your red wine, in a street cafe, while watching street performances. Coble stones, Lawrence River bank, French language, street cafe ... you can taste France right away.
And if you have time, please visit Quebec City. Probably 2-3 hours driving north Montreal, Quebec City is the home of Chateau Frontenac (now hotel), one of the finest French architecture in Canada. Really neat city, and UNESCO chosed to protect the area.
PM me if you need more info. You are so lucky, I really enjoyed my time in Montreal.
