Reset Router!

You might try going to start>run>Type in CMD, and press enter. . In the windows that opens, type in IPCONFIG.
That should give you your IP Addess, Subnet, and Gateway IP.
Make sure the Gateway IP matches what you are typing into your IE addreess bar.

If your IP addess for your machine, is not in the same range as your gateway, i.e. your machine is 169.xxx.xxx.xxx, and your Gateway IP is 192.168.xxx.xxx, (XXX being any numbers from 1-254), you won't be able to access the router.

If this is the case, you would have to set a static IP on you machine, and then put the Gateway IP into the IE address bar.
Basically, if the IP address of your gateway is 192.168.1.1, your machine IP would have to be 192.168.1.xxx to connect to the Gateway, using the Gateway IP in the IE addess bar.

Hope that helps some. If you need help on setting a Staci IP on your machine, click here.

http://www.answers.vt.edu/ask4help/connection/vtkb697.htm

BTW, if your machine IP is 169.xxx.xxx.xxx, there is a good chance you disabled DHCP. That 169 ip is a default one XP gives itself when there is no DHCP server avaialble.

If this gives you access to your router, you can look thru the options to reset to factory defaults. Trying to find a manual that matches your router.

Good Luck