How to use a wireless router as a switch

We have a netopia wireless DSL router with four computers hardwired and two wireless. Add port are taken on the netopia. I would like to add two additional hardwired computers to the network (we are a non-profit with no funds to purchase wireless PCI options). We have a netgear rangemax wireless router just lying around. How can I add the netgear wpn824N as a switch/hub, with the two computers hardwired, without it interfering with the existing wireless configuration.