In no particular order...
Alien Breed 2D series (NOT the 3D one)
Lemmings 1, 2 & 3 - oh no, it's addictive!!!
Menace - my favourite shoot-em-up. I love the music.
Red Storm Rising - dated graphics, but I still love to play.
Ports of Call - addictive as hell.
Speedball 2 - used to play "league" with buddies & beer!
Kick Off 2 - same reason as speedball 2!!!
Bards Tale 1 & 2 - who needs sleep?
Cannon Fodder 1 & 2 - kill, kill, kill!!!
Civilization - forced me to buy a PC when Civ2 came out!
Syndicate - more killing!!!
X-Com: UFO EU AGA - Gerry Anderson's UFO Series in a game.
Xenon2: Megablast - another damn good stoot-em-up.
Wings - Up, up and away!!!