Are you with NTL by any chance? I brought a Belkin router too a while back, and had nothing but grief! I would set it up, and it would work for a couple of hours, and then suddely, it would just stop working! In the end, i put it downl to NTL, but i then brought a Linksys router, and have'nt had any trouble since! Its been fault less since!
did you double check your settings in router.Try a hard reset and start over.Check different ports with working pc (to see if you have a faulty port).And some routers are not compatable with certian routers!!!!!
Have you phoned Belkin? part of the reason to buy their gear is the support they give. I had a few problems and they were VERY helpful. At one point I allowed their technician to have remote control of my computer to speed up the fault diagnosis after which we soon had my network up and running.