I believe the default Belkin Router IP address is 192.168.2.1
Open up your Internet Browser, and type in that IP address. This will open a web-based configuration for your router. I don't think the Belkin routers are passworded by default, so just leave that blank (You can change it later to anything you want, and probably should).
That will get you into the configuration and let you turn off the wireless. You could also restrict your access so that you can not allow some PCs to connect, instead of just turning off wireless all together.
Edited, Mar 15th 2009 2:21pm by TirithRR
Can't sleep, clown will eat me.