Actually, I would have the switch connect to dedicated wireless router and that to the modem. I find that the wireless in the modems are less that reliable and you have more control over your dedicated router. This way, the router connects to the modem for internet access and assigns the clients all the ip addresses.
192.168.1.1 (modem) -> 192.168.0.1 (router) -> Switch -> 192.168.0.2-254 (clients)
It works best if you put the modem in bridge mode. Either way the router is in the wrong position. Either place it how Airheadq said or get rid of it.