Moving to Toronto from London UK

Hi all,
I hope I can get some advice from all you good ladies (and gents).
My husband, myself and our 11 years old son are thinking about moving to Toronto from London. My brother in law lives just outside Toronto and he has been living there since Protected content . We have been to visit a few times and every time we go to visit we say we would like to live there. However, every time we visited was during summer, so I wonder what our opinion would be during their winter. My brother in law says that winters are not as cold or as long as they used to be 24 years ago now. He says they are much warmer and the really cold temperatures last for max 3 weeks and that's all. Well, my brother in law is usually very positive and happy go lucky, so if you have any other opinion, please let me know.

Furthermore, there are three other tings I need your help with:
1. Average salary for Senior Project Managers in Investment banks. My husband has been working for investment banks for the last 16 years. I tried hard to find what his salary would be in Toronto (permanent and contractor), but it is almost impossible to fin out. If you know anything at all, please let me know. Furthermore, my job is in PA and HR as HR Coordinator. On average, what are PA's salaries in Toronto? Again 20 percent up or down in guessing is OK. As long as I have some kind of a number so that I can figure out how much we can bring home and what our living standard could be there compare to what we have in London right now,
2. Schools and where to live. We like Oakville, Bront and South Mississauga. We also like North of Bloor Street and Beaches, but we are realistic and know we cannot afford anything there right now. How do I find out if school is good? I would look around Oakville, Bronte and South Mississauga, even though my brother in law says that we should look around Uxbridge, Pickering i Stouffville as well. However, my husband likes rowing and we would really like to be near the lake, however, we are open to all options.
3. And finally, the quality of their National health Services. Is it as 'good' as current UK NHS is or is it better? We are lucky to have BUPA private in UK as well, even though we use NHS most of the time, but if we really want to see specialist within 2 or 3 days we go BUPA. We know there is no private option in Canada, so please let me know your opinion and experience regarding National Health. I have some auto immune chronic illnesses for which I need one year and 6 months check up. I wonder how would that be using national health and not private (currently most of my checks are still done using private).
4. Any other information you think I should be aware of.

Thank you very much for all your help.