only you can really know that. its what you want to do... need a bit more information, like what is your preferred choice of subjects (you only specified for two universities), what type of university you want to go to, what area etc. i decided by a) what the area was like. i decided i wouldnt go to any university which didnt have green spaces near by, i'd go crazy moving from a village to somewhere which was completely concrete b) i wanted everything to be close by so i picked mostly campus universities c) ideally i still wanted to go somewhere relatively big to experience life in the city d) i wanted to have a year abroad e) went to the place to see what it actually felt like and pictured myself living there f) i looked at what societies they had
those are the kinds of things i looked into and that doesnt even touch in on the course details.... i have to be honest, i didnt look too much into how the courses differed in terms of how they were taught because they all said basically the same things, but if you want to do history which you said for leeds & sheffield i guess seeing what their research interests are can be a good decider. league table positions (although i wouldnt base it too much on this...), stuff like that.
if you really want a suggestion... i loved the feel of birmingham. they should be AAB for a joint honours i think... but the thing is, you have to research it yourself. you know what you want.... i started looking early and so by the time it came to applying i knew what i wanted because things just mulled around in my head and i kept coming back to certain things. sometimes that's the best way to go about it rather than panic...