Both can be great cities and have different things to offer. I would try to visit both and see which one you enjoy more. TO is like a racial mixing pot, you get people from all over the world, so it has a pretty unique culture, but it's a pretty big city. Not a lot of outdoors, I didn't find people to be the friendliest. If you like living in a big city it might be worth it.

Vancouver is big, but more spread out. The downtown core isn't huge. It's in the Fraser Valley so it's beautiful pretty much no matter were you are. You have these bit mountains in the north and east. Not quite as multicultural, it's predominantly white/Asian(/Indian). I live in Delta which is a 35 minute drive from downtown with no traffic or closer to an hour wirh traffic. There is lots to do, especially if you like the outdoors.

Weather is pretty drastically different. TO has hot hot summers and cold cold winters. Expect a bit of snow but mostly it's just freaking cold. However, it's typically still nice sunny blue skies in the winter. Vancouvers winters are much more mild; we didn't get any snow last year where I live. It will get close to 0, but we play outdoor soccer year round so it's certainly bearable. Winters can feel long when it's just grey skies and rain though; part of living in a valley. Summer's are beautiful, hot and humid. Luckily there's no shortage is beaches and lakes to go cool down in.

Looking for anything in specific or does that help?