Then I recommend the Musée d’art Contemporain de Montréal. I’ve added the link to the English site, but there is an option to view it in French if you prefer. Incidentally, if anyone can figure out how to put in the appropriate accents in WordPress, I’d love to know. [edit: Many thanks to thatspoiledrat, who kindly explained it for me!!]
I used to visit this museum with my mother when we lived in Montreal- I always really enjoyed it.