I have the wireless installed, and secured, but it bounces between connected and not connected. It's not a distance thing, right now the wireless computer is 3 ft from the router. Is the router shot? The wired part works fine.
Did you name your setup "linksys?" I did this and my setup kept getting confused with my neighbor's setup. My PC wireless adapter could "see" his wireless system. He had used the same name. My system could not figure out which system to use.
What kind of equipment are you using? There is a documented DHCP bug with the WRVS4400N that only affects the wireless side of the device. The only known workarounds are to back rev the firmware to 1.0.16 or to statically code the IP addresses on all of your devices.