You can live in a lot of different areas around USC. You can live downtown, around the campus (decent, but you can certainly do better), West L.A., Pasadena, and the Mid-Wilshire area.
USC is in an urban area, but much of the immediate area surrounding the campus is filled with student housing. The ghetto is south and east of the campus. You really shouldn't worry much about this, as many healthcare institutions are in urban/poverty stricken areas.
Good luck!