[mister J]

Freespace 1 and 2, especially 2.
Descent 1 and 2, especially 2.
Starcraft

Super Mario Brothers 3 (I spent hours on that game.)
There were also numerous hacked or pirated versions of 'Mario' that I enjoed immensely as a kid, one had Mario with a hammer, one had him turn into a ball/kangaroo...
Mrs. Pacman
Dragonball Z Super Butoden 2
Tetris - way back when my country had 8-10 hour blackouts daily, THIS was the only way to pass the time.
There was also a game for an Atari console I once had (forgot which model) which was basically a hide and seek game.

[TrenchardsLoveSock]

Going back to my ZX Spectrum days:

1. Elite
2. Jetpack (but NEVER the sequel)
3. Chuckie Egg


Nothing outstanding that I remember on the Atari ST apart from Elite Gold (filled polygons, OH YEAH).


Early PC stuff (joined the bandwagon fairly late):

1. Baldurs Gate
2. System Shock 2
3. Dungeon Keeper (don't remember if it was 1 or 2)

[Mika]

Ah, Jetpack

I remember playing that one too. I never knew if there was a way to "win" the game.

Mika

[TrenchardsLoveSock]

Ah, Jetpack

I remember playing that one too. I never knew if there was a way to "win" the game.

Mika

It was the EIGHTIES, you very rarely 'won' games.  You just kept getting higher scores until you ran out of lives or you got cramp!