Can't share data between two routers

Ok this is probably a simple fix that I'm just to oblivious to figure out. I have a large two story house and in order to have the whole house wireless I had to install two routers (Linksys WRT54G & Belkin Pre-N) on the home network. In order to get them to not conflict with each other I had to place a switch in between them (Nexxtech Switch). So basically I have the internet going through the switch first followed by using the switch as a "splitter" with a direct connection to both the routers.

Now my issue with this setup is that the two PC's on the right side of the house are connected to the Linksys and other PC's on the left side are connected to the Belkin. A total of 5 PC's in all. However when I go to network a folder between from one PC on the Linksys to the one on the Belkin, I am unable to even see the list of available shared folders on the network. But I can see the folders shared from the computers on the same router as the one I am on. It's sounds confusing but is there any way to fix this mess so I can share from any PC to another? Any advice would be great. Oh and just so you know the switch has no built in web page but the routers do. All PC's use Windows XP Professional except for mine that uses Vista Ultimate.

Is there any to do this the other way around like where it's DHL then the Belkin followed by the Linksys? It would take me hours to get to the linksys and swap it around. I hate going into the attic.

Yes, either way will work. Just turn off dhcp on the second router.