[evulish]

How does your computer get assigned an IP address? Via DHCP? If so, that may be the problem.. might try to open up cmd.exe and run this:

ipconfig /release all
ipconfig /renew all

That should get you an IP address if you're using DHCP. If you're on a network, and that ipconfig stuff doesn't work, try manually assigning an IP address. Find the IP of another computer on the network (run ipconfig /all on the other computer and it'll be in there) then change the last number. I don't really remember how to set an IP manually in XP, but it's somewhere around in network devices or something. Once you get the IP manually set, try pinging the other computer's IP address. Since I don't really know how you're connected to your network and am doing all this from memory, that's the best advice I can give you.