Went last September. Travelled from my home in Birmingham to Bruges, all by train/Eurostar. Really is quite a nice journey if not a bit too long.
As for things to do, just have a potter about man! It's a fairly big City with things to do everywhere. If you like a good drink then all the better really, that's why we went. Just don't underestimate the beer there... really will floor you if you don't take it easy.
I will say that the idyllic scenery is somewhat counter acted by the sheer amount of tourists bustling about. My friend hated it for that reason. Said it felt too much like a time capsule by design, which I suppose is somewhat true.