Slow Web Page Loads with Vista Home Basic

I have a new system with Windows Vista Home Basic. In either IE or Firefox, pages like Google and Yahoo load fine, but almost all other web pages take 3-5 minutes to completely load..

This computer is using the same connection that my old (now dead) XP machine used and is on the same router as my XP Pro laptop, neither of which had any issue.

So far, the manufacturer eMachines has been no help – only recommending things I had already tried and suggesting that I reload the machine.

Any ideas?