Are student halls and universities in london safe to live?
Yes, however, like any other place, you must be aware of your surroundings, practice common sense, avoid dark places or walking alone at night, avoid risky situations, be courteous and polite, and learn about the security system and policies in place at your university.
why wouldnt it be as long as you dont mess with anybody your good
Yes. I would say that most places in London are safer than a lot of major cities in the world. There are some people who like to get drunk and be silly; just make sure you stay out of their way. There are some special days when people are particularly out and about - like the May day, soccer events etc. Try to stay in if you can. If you are going out to experience those events; be prepared to see some drunk people. Keep you wallet in a front pocket is always a good idea. Many pick pockets on tubs and other crowded places.