Bangor is amazing. You have Snowdon on your doorstep, the Menai Strait and apsolutely awesome Beaches 5 mins away on Anglesey.
As far as going out, you have you 3 main clubs, Time, Academi (in the SU) and Octagon. They all are fairly good, and regularly bring big named DJ's in including Mr Scruff, Eddie Halliwell, Rob Da Bank. Nightlife is definately no London or Manchester, but you have loads of Bars to drink in.
Basically Bangor has something for everyone, possibly the best place in the UK in my opinion.
12-14 Holyhead Road, Bangor, Gwynedd LL57 2EG