I need an A/V switch that I could use to switch between my whole collection: which includes: Sega Genesis/32X/CD SNES NES N64 Gamecube Commodore 64 and a PC running Stella with Atari Joystick to USB adapter/ If possible, I would like this to be infared controlled, like with a Logitech Harmony remote.
An AV Reciever could do all of that, especially a high end one. (Assuming you have a HDTV): Connect what you can via component, the rest via composit eand get a DVI - HDMI cable into the reciever's HDMI, then HDMI out to the TV. Of course you'll need speakers, and make sure the reciever can route the analog inputs through the HDMI port. Or if you have an SDTV and a PC with Svideo\composite out, just use the composite inputs instead.
Be prepared to pay well. The cheap ones introduce plenty of noise into the picture. The component one I bought went straight back to the store when I discovered how bad it was.