Sell it all back to Super Potato for enough money to buy a McDonald's value meal?
Keep the systems that are disc-based and lack backwards compatability.
The gameboys you can get rid of... since DS plays GBA and the others can easily be emulated. Gameboys make great gifts to younger relatives or children's charities. The Gamecube will be obselete when you get a Wii... unfortunately, it's equally worthless to everyone else for the same reason: again, donate it to a hospital or give it to some kids. PS1 is obselete because of PS2... you could get $10-20 for it... but chances are you're better off donating ALL of this stuff to a children's hospital so they can build a gameroom or giving it to younger kids in your family to turn them on to gaming.
There aren't Super Potatos in the US, so I guess you can't even get a value meal