Wolverhampton has a bad reputation, but my own experience of it has been fine. There's not a great deal there to be honest, but it's a nice enough place around the centre, nothing special at all as I say but it has all the basics. I'm sure it has some bad areas, but the same could be said about any city really. There are pretty good transport links (tram, bus, train etc.) so you could easily get to Birmingham for instance if you wanted more around you. So yeah I'm not going to suggest it's some sort of paradise, but it's not a wasteland either. The Uni is nice enough too, quite nice buildings, the library is very useful and the people there helpful, there are plenty of facilities etc. I haven't been to Hull so can't comment on that, but consider both.