Can't hook up digital converter box to a/v selector?

I moved and can't remember how to set my tv back up again.The selector has one out and four ins, all with the yellow/red/white a/v cables. The converter has an out to tv threaded coax and one place for the red/yellow/white a/v cables. The tv has a threaded coax place in the back and one set of yellow and white av cables, we always leave out the red since there's no place for it, in the front. I have a screwless coax cable but I don't know where it came from, but i think it might have been hooked up somewhere but I don't really know. What am I doing wrong? I'ts getting annoying to have to unplug everytime I want to play Wii or whatever. I tried looking up the brochures but they are both RCA and RCA claims I need no manual for the converter and the link to the selector's brochure is dead. Please help!