Statistically, Nottingham comes out badly. I believe it tops the tables for burglary, and the student areas are probably the worst, as these areas actually attract burglars. Students are perceived as well off, and a typical student house may contain a huge haul of consumer goods that can quickly be turned into cash; every bedroom, and even the lounge sometimes, could contain an individual's stereo, telly, video, DVD player, computer, CDs, ipod etc. Students also follow a more or less predictable pattern - for example, the very beginning of the academic year, Christmas and easter are favourite times for break ins. Plus, many student properties are easy to break into, as they often have few security measures in place.
As for personal safety, I felt that the areas I lived in got worse during my time in Nottingham (I lived in the Arboretum area and then Forest Fields from 1992 till recently). I can't say I experienced too many problems walking home at night, but I stopped crossing the Forest recreation ground at night, as I was hearing too many stories of people getting ambushed there. I'd say that the red light area is dangerous for lone women at night, more from the people the area attracts rather than the prostitutes and pimps themselves.
having said all that, you could probably say the same about any large city in the UK. Out of all the places I've lived, I felt most uncomfortable in Leeds during the early 80s.