I don’t know much about Leeds, but I do have a friend at Warwick and considered going there myself. From what I’ve gathered, the campus there is in the middle of nowhere pretty much, so if you’re looking for things to do, I’d go with Leeds. If you’re worried about employment prospects I wouldn’t necessarily choose what you might consider to be the more “prestigious” of the two. It might be worth checking their websites and some leaderboards to see what graduate prospects are like for the courses you’re interested in. Again, you could see what the standard of teaching is for those courses on leaderboards.
Ultimately, Warwick is a campus uni while Leeds is a city one. I’d say Leeds would probably have a better social life for students with it being in a fairly large city. But campus-based unis are alright if social life is something you’re considering (i.e., student unions are usually better, everything is in one place, etc.).
Anyway, hope this helps.