The first thing that comes to mind is the firewall on your computer. It is easy to accidentally tell the darn thing to block access to the web. I suggest you temporarily turn off your firewall and see if that helps. If it does, then look into its settings and see if it has blocked http service or blocked your web browser program.
I would try another web browser to eliminate the possibility that it is just the browser program having a problem.
Are you experiencing the same problem with the XP computer as well? If so, it suggests a problem with the router. If you can access your router's setup page through your web browser, look for a "renew" button (likely in the "status" area). Renewing your connection to your service provider may well fix the problem.
It would be interesting to know if it is a DNS problem. You might try running "Command" from the start menu to get a DOS window, then trying to ping web servers. For example, you could enter
PING 75.125.148.76 and see if you get an answer.
Then try PING www.3gart.com and see if you get an answer.
(I picked something obscure that won't be cached on your system)
If you get a return from the numeric address, but not the www one, then you likely have a problem with DNS.
While you are in the DOS window, you might try entering the command
IPCONFIG /renew
This will renew your computer's connection to your router, perhaps clearing up a problem there.
Post your findings and I'm sure the folks here will help!
