I guess I'd have to rate the best games on the basis of the time I spent playing them rather than them being graphically good. So with that in mind, here's my list
Microprose Grand Prix 2. For me the best of the 4 game series, and by far the best F1 game ever.
Civilization 2. Used to play this for hours and hours, just pips Civ3.
X-Wing. Best of the Star Wars games.
Sim City 2000. Spent many a night playing this only to have my city destroyed by some disaster or another at around 3am.
Championship Manager. Not sure which version to pick, I'll go with 01/02. A life ruiningly good game.
Wolfenstien 3D. One of the original first person shootemups, just beats Doom because you get to shoot Nazi's.
(All PC games)
If you want to go even older then Tetris and Breakout probably belong in the list somewhere.