I wouldn't go to a uni just because it wasn't a partying uni!!! Go based on it's facilities, the town/city and most importantly you're course. Every university will have students who like to party and those that aren't too keen. Even if you don't, I would really advise going out for freshers week though. No one knows each other so just take the opportunity to act less shy and talk to more people :-) That's how I met my best friend at uni - she was at the bus stop and I asked if this was where I wait for the campus bus. She said yes and we got chatting.
You never know though, you might warm to going out. I never used to be the dancing type but I just went for it in freshers week as no one knew me so they didn't know how awkward I was before. I don't LOVE going out, but once I am out and had a drink I don't mind it too much. I still can't wait to get in bed with a nice film tho!
Oh, and sport doesn't necessarily have to be a big part of uni if you don't want it to, but it is great to meet people in a less awkward way. When you go out, the focus is on talking to people but when you join a club, you make friends WHILST playing. And there are sports clubs that don't involve too much running about (fencing, snowboarding, film, pirate club, scuba diving etc). Your fitness will improve anyway :-)