Well I can tell you that New College is about a 10 minute walk from the Medical Sciences Teaching Centre where a lot of medic lectures take place (I know as my first year Psychology lectures were all there) and I believe that area is also where a lot of the medics spend their hours. The only downside of that is that you have to walk past Mansfield to get there, which is tough when you're hungry and you can just smell the food that they are prepping for lunch...
Our library isn't open 24 hours a day, but 8-12, although this upcoming JCR Academic Affairs rep wants to prolong this around exam time I believe. I personally don't see this as a problem, but then again I don't really work in the library (although last term I discovered that it is a nice place to work, and especially useful the day before a deadline to prevent too much procrastination which I usually do far too much of...
I would say the student life is really good - there is so much that you can get involved in (although if I'm honest this would probably be the same of all colleges, shhh.... )
When we first arrived there was a New College freshers fair as well as the student union one, so you really can get involved with whatever you want. Also, I really like our porters - which is really important as you will probably be seeing a lot of them (especially if you are like one of my friends who locks herself out of her room all of the time).
Personally I like New College because it is really central but also quite well hidden - you can really easily get to places without having a completely busy road like the high street straight outside. Plus, we have the Harry Potter tree and a mound that when you clap in front of it it squeaks - who could want any more! :P
In terms of sports and music - I have a friend who plays a lot of football (at New College), and I know that each Trinity term (3rd term) there is after-tea footie where they just go for relaxed matches after dinner. We recently purchased the official Rio football for about £100... so football is popular (it was put forward as a JCR motion and no one objected)! There is also a woman's football team which I know one of my friends has played for from time to time. With music, as at Worcester if you are of a certain standard (at least grade 8 I believe) then you can get a music scholarship I think - I remember getting an email about it at the beginning of first year.
The good thing about Oxford is that chances are you will actually end up loving whichever college you end up at (but New College is best, of course