tcpip issues?

I've got 3 computers set up on my network, mine works fine but my mom's computers' internet magically quit working. Weird.

I checked all the network settings and mirrored mine over to hers, its totally stumping me because IE and FF wont load any pages but Automatic Updates and Spybot updates work fine so TCP has to be working to some extent. The local network is ok, I can browse to and from her computer. If I open her network connection status window it shows like 700 JILLION packets sent and only like 8 recieved, unless I update something then it gets up to like 2500 or so. Seems like it KINDA works but is getting plugged up somewhere. In any case I'm tired of screwing with it and I realy dont have a clue what to do at this point. I already erased all of the old network settings and just added the local connection and reinstalled the TCPIP and IPXSPX protocols with the right settings.

did you bring down the firewall(s) and check the router settings?

yeah, i dont see any reason for it not to be working right. the router doesnt discriminate any of the computers, all of'em get assigned IPs automatically and everything. No firewalls.

what happens when that computer is plugged directly into the modem?