Hi there

I can give one way of trying. If you turn internet connection sharing on the the wireless card in your PC, it will then alocate IP addresses via DHCP(i think). Then turn off DHCP in the Netgear but making sure it has a IP address in the same subnet as your network(so you can still access it). If you plug the xbox into the switch side of the Belkin wireless router it should be able to request an ip address and the wireless card on your PC will respond with the correct gateway.
This works with most wireless routers unless there is some rule blocking traffic between the switch and the wireless side.

Good Luck
Dale