Vista will pick up settings via DHCP, which currently it refuses to do
That's a "feature" that many people ran into -- supposedly it works OK on all microsoft networks, but not very well if you have a hardware router doing DHCP for you.
Luckily, there is a fix for it.
A quick google returned the following (among many similar pages)
http://thedaneshproject.com/techblog/archive/vista-not-working-with-dhcp/