Update, I got the network drives to work now, there were three things that were blocked in the firewall I'm using so I allowed them and now it all works. :S Worked fine before with them blocked but not on this router. That's that problem sorted now anyway.
Still got the conflicting problem when trying to use the internet. Basically the XP computers work fine, the W7 computer doesn't, and when the W7 computer is on the XP computers don't either. I'm guessing there's some kind of conflictingness going on there.