The Student Union is pretty lively and easy to get to, though people tend to branch out after freshers. You have the choice of pubs/clubs in Leamington Spa, Coventry or for a big night out you can get the Uni Express to Birmingham for Gatecrasher etc. It's not the best in terms of nightlife, but it's certainly not bad.
On a more-important-than-nightlife-note, your choices severely lack an insurance option. You need somewhere below AAA to fall back on if you don't get your grades.