If you get an a1200 with HD, then it will play most a500 titles + the newer a1200 aga games. The only way it will play c64 games is through a emulator and i think you would need a accelerator upgrade for that.
Using whdload with a HD will not only enable you to run most a500 games, but it will also make the games load in seconds! And you can start them just by clicking on the game icon in workbench.
So i would recommend that you get a hd and a cdrom for that a1200. It can play some a500 games even without a hd. You do this by holding down both mouse buttons during start and then select it to emulate ocs graphics.
