The whole point behind building an arcade machine is to play the games you played way back in the late 70s and early 80s. You can't achieve this using a console system or a computer running an emulator because the arcade machine and it's controls are an essential part of your interaction with the game. And (unfortunately) you can't even do this by walking into a modern arcade parlor, since you'll find all the quality games have long been replaced by fighting and dancing polygons which resemble the latest Xbox/Playstation2/whatever console games. Even if you could find an old classic machine tucked away at the back of the arcade parlor, you'd have to bypass hordes of dangerous teens armed with knifes and handguns.
Some notable favourites, played regularly: Stargate, Defender, Joist, Track 'n Field, Moon Patrol, Galaxian, Galaga, Robotron 2084, Space Invaders Part II, Shinobi, Bezerk, 10-Yard Fight, Donkey Kong, Asteroids, Ghosts n Goblins...
