AFAIK the Belkin don't have a reliable UPnP implementation, thus port forwarding is probably your best bet. Find your model here http://www.portforward.com/routers.htm the most important step is the 1st one which is setting up a static ip.

BTW if you're running xp sp2 then see MS & 3rd party patches to improve your connections.

Sorry sleepless ... I'm a bit slow today ... lol