Raised two kids in Montreal from birth to middle school. Safe, inexpensive (in particular housing and electricity, which important for heating), easy to integrate (except the East part of town). We never had a car (rented for day trips), so you can save that as well. Winter are cold and long, but kid are good with it. Good communications in town and to other places. We stayed within city limits about a dozen short blocks for the subway. Kids learned French for life.
Drawbacks: few kid amenities for a city that size: no zoo, science museum is for adults, language politics get annoying
Trust me, you don't want to move to Alberta these days. It's a dumpster fire. The local economy has imploded since oil dropped. 30% of the office space in downtown Calgary is completely vacant.
One does not have to take up permanent residency in Canada. You can work on visa. Then, you can send your kids to an English speaking school. Of course, if you send them to a private school, you can choose among the best English schools in West Island, West Mount or Hampstead, if you want to. Even if you are a Canadian citizen. No restrictions are placed on private schools. They cost anywhere b/w 10k and 25k. per year.
Also, as a foreigner, you will have several years (I believe 5) of paying virtually no provincial tax. Then, you can get PR (permanent residency) and Canadian citizenship right away, since you've lived enough. Even years living in Canada on work visa count towards citizenship. One year counts as 6 months.
If you don't like to pay provincial tax in Quebec, you can always move to Alberta where the taxes are low and the salaries are high.Good luck enrolling your kids in an English-speaking school.
All in all, it is a little Third World island within North America.This person is dumb but raises one good point. If you or your spouse did not attend an English high school in Canada then your kids can't go to any English school that receives public funds. That includes most of the private schools in addition to all the public schools. Of course there are many excellent French schools, and if you did attend an English high school in Canada the policy doesn't matter, but it's something to be aware of.
Alberta is in for a bad time. The province is almost totally reliant on a single sector that is in a death spiral and has close to zero savings thanks in part to their low income taxes all those years. Your salary might be lower in Montreal but at least the value of your house won't collapse all of a sudden because the price of oil is in the toilet.