Nottingham's international reputation is far superior to that of Leeds. It's a very strong University and the academic rigour of the course is very high here. I would say that in terms of the campus life, Nottingham has a very nice and large campus. You won't be disappointed by that.
As far as the city goes, it's big and there's plenty to do. You can take a bus into town for £1.40 and if you are a group of around 5-6 people, then a taxi is worth taking as it's between 5-8 pounds to and from city centre to University Park.
At the end of the day, your choice should be based around the course and that is it!