Answer to: N64 Wont work, Tried tips from this Site, none workedThe issue here, I believe,is the AV cables. Trying replacing those first, then go from there.
Answer to: It turns on and the music plays but the screen is incorrectChances are that it's a problem with the RF cable. The first step would be to replace that and go from there.
Answer to: NES pin connecter compatabilityI honestly don't think it will matter, but chances are you don't need to replace it at all! You need to remove it, clean it, and bend all of the pins back in place so that the carts connect to the system better. It takes a bit of time, but saves money.