You'll pick up the Uni connection no problem, because you're so close to the wireless connection at York House, so you'll have ridiculously fast internet access.
Parties in Norwich House...Hmm...I went to 2 last year, both of which were really, really good. The rooms there are quite cool, and you'll be able to sleep fine in them. You're probably going to be closer to your lectures than anyone else, and that's a plus on those mornings when you're lying in bed contemplating sleeping in. Norwich House is cool , but party central is East Slope, and I'm not just saying that because I lived there, it really is.
There's a load of regular students there, it isn't just full of international and mature students! Norwich House and Brighthelm have rooms/houses allocated to them, but they're not forced to live there, so there is a good enough mix.