Sharing through a router

My Win98 systems shares a cable modem through a router. I've noticed there are never any uploads monitored on my computer. I would like to share my files back to the network. Anyone have and idea of how I might make this work?

My thought is that the router must be acting as come kind of firewall that makes my Limewire invisible to others.

Is the Force IP a feature I should be using?

Thanks in advance

Jaylaca