Quick question, How old is that router? There are been many improvements to Vista, maybe it's having a problem handling it. You can try the "Internet Connectivity Evaluation Tool" (Microsoft) or try the "Diagnose Wizard". Have you tried to assign IP address to router and computer manually? There are other problems perhaps to look into- 3rd party software, security firewall. I've heard that some people had a great response using "Network Magic 5.0", but that was a year ago.