You mentioned that the printer is using one of the existing ports on the router? Probably too late now, but why do that?
My printer is connected to one of the PCs on the network, and shared with the others. That works just fine (as long as the PC with the printer is switched on, which it always is).
I tried (briefly) hooking two routers together and had some "fun" with the DHCP addressing. The fixed machines no longer use DHCP, but have their own allocated addresses (up in the range above 192.168.8.102). The laptop and the Ipaq use DHCP to the WiFi access point, and it all works smoothly. Then I went back to one router anyway.