iOS 5.01 (or 5.1?) is out now, to be honest, i'd just upgrade. As long as your phone is backed up beforehand then there's nothing to worry about. And I think if an upgrade broke it (and you couldn't restore) book in to an apple store and they'd sort it for free for you as they did for Mr A's back in July, and that phone was 18 months old
Yeah, I'll have to give it a go soon the buttons getting worse. Once I've sorted out these computers I'll give it a go!