To expand on what Westside guy said, your best bet is to use your current wired router for IP address distribution and network address translation. Then, use a wireless router configured as an ethernet-to-wireless bridge (or maybe use just a standalone ethernet-to-wireless bridge). Basically, this setup would assign the routing duties to just one router, in this case, your ethernet router. The purpose of doing this would be to allow all computers on the same subnet, thus allowing them to see each other.
I'm fairly certain you can do this with most wireless routers. With Airport Extreme, for example, you simply open the Airport Admin Utility, click on the "Network" tab, and turn off the "Distribute IP addresses" option. When an Airport base station is configured in this manner, connected to an ethernet router, the Airport merely acts as a bridge between your wired network and your wireless network. All IP address assignments and network address translation is handled by the ethernet router.