You shouldn't have to adjust the wifi router to fit your phone: you should be adjusting the phone to fit the router. Otherwise, you may end up knocking everything else off the network!
What I'm thinking now is backward compatibility. Is your router B/G/N compatible? I know some N-routers coming out will not connect to a G-speed device like your Optimus (few phones are N-speed capable). I had to replace the first N-router I bought because it wasn't backward compatible.
I suppose now we need to know more about your router, and what the Optimus is doing when you try to see the network and connect.