Would be about a 45 minute commute. Rosedale is a rich neighborhood that's just outside the border of the downtown core.

I don't think you really NEED to be close to the parade. The other stuff going on at night is kinda scattered throughout the city anyways. So if you found a great deal/place you like I don't see much reason not to stay there. But you'll have to take a subway and then streetcar/bus to get to the parade.

This would be your commute:

https://www.google.ca/?gfe_rd=cr&ei=p3LYVvLcFIqN8Qe9zKHQBw&gws_rd=ssl#q=rosedale+station+to+exhibition+place+ttc

Probably more like an hour from door to parade.