Oh man, this is like asking me to choose between my kids. Can't do it.
I'd probably rank the Celts and Sox at the top if you put a gun to my head. I never played organized footbal, but grew up going to every Pats home game for many years. I spent a lot of time playing basketball and baseball and love both games for different reasons, and love the local teams for different reasons.
Uggghhh...tough question. You'll have to put that gun to my head to get a true answer!