Pac Man - Classic

Firstly, there's this yellow blob (with a mouth) which has to roam round a maze swallowing little pills. Meanwhile, four ghosts (named Blinky, Pinky, Inkey, and of course, Clyde) are chasing you as you listen to a high-pitched wailing noise.

Original Fun, Original Graphics!

Space Invaders - Classic Arcade

It's a simple game with simple graphics, but it has one of the most vital assets for any computer game — gameplay. Modern games seem to forget this with their fancy "3D graphics" and "millions of dollars". All you need is a pointy green thing which shoots white stuff at a rampaging invasion of wobbling blobs. They don't make 'em like they used to.