My own Montreal experience has taught me that it is very difficult to find someone in Montreal who does NOT speak English. There should be no problems in communicating.
It's a world class city -- so lots of shopping opportunities in the downtown area. The old port area is filled with boutiques and other shops that line the cobblestone streets. Rue St. Catherine, while "worldly" in more adult ways, is where you'll find the downtown shopping malls.
As for attractions to see -- we fell in love with the Biodome at the Olympic Park. They have converted the velodrome (the site of the 1976 Olympic bicycle races) into an aquarium/wildlife habitat/environmental science centre. I found it to be much along the lines of the Aquarium of the Americas in New Orleans, but without the deep water tanks.
Getting around Montreal is dead easy using underground Metro system.
Whatever you find yourself doing -- enjoy your stay in La Belle Province!