From a backpacker's perspective, Leeds seemed a pretty nice place some years ago. Relatively quiet and laid back. And obviously the Royal Armouries museum is a major attraction if you're even remotely interested in arms and armor. I think the kids would love it.

Manchester and Liverpool were different, though. With much of the once thriving industry in ruins both cities were in a state of decay sort of when I was there. Also, an unusual percentage of not quite so friendly people (gangs) in the street. My travelling buddy and I nearly got in a fight in Manchester (we kept a low profile all the time and were never looking for trouble). Liverpool wasn't much better, you could definitely see there was a serious drug problem.

At least that was my experience as an outsider on a brief visit something like 5 years ago. All in all, I'd probably rather live somewhere further south if I could choose freely. Or some place in Scotland. Never mind the weather, that is one of the few places in the world where I really did feel welcome and comfortable.