toronto/montreal/ quebec
 

We are going for 2 weeks in June. How should we divide our time?

What are your interests?

thanks. Sightseeing, walking. The usual tourist stuff.

With two weeks to spend, I would recommend that you add Ottawa to the mix. I regard it as one of the most underrated destinations in North America. Toronto and Montreal are big cities and so you will need more time just to get a decent look at what they have to offer. (You can work a day trip to Niagara Falls into the Toronto leg, too.) I would give Toronto four days and at least three for Montreal. Quebec City is worth a couple of days, as is Ottawa. With travel time, that will just about consume your two weeks.

I would agree with Flyboy - don't miss Ottawa if you are doing Montreal and Toronto. Ottawa is picturesque, has great bicycling trails, and it's museums are world class. Try and spend at least a day here.
Although Quebec City is the most scenic, it is small, and 2-3 days should be plenty.
Montreal is all about dining, nightlife and shopping. Lots of interesting ethnic neighborhoods, and great for strolling around. There's always some type of festival going on. Not particulary scenic or full of museums, but a very fun city. At least 3 days here.