Mike Tyson's Punchout - Best boxing game ever, 007-373-5963
Metal Gear - This just revolutionize daction adventure games with a great story line and great equipment and weapon options
Metroid - I was so pissed to find out it was a chick all along, the best side scroller at the time
Gauntlet - The best 4 player adventure game ever made
Altered Beast - Welcome to your doom, steroid powerups mutants and zombiez
Street Fighter 2 - Best fighter game controls to this day
Mortal Combat - best finishing moves ever, if thrill kill were ever released it would take the title away from MK
Carmageddon - The best driving and killing game ever, electrecute powerups while listening to Fear Factory
Postal - The most disturbing game, yet fun in that really dark way
Doom - The original FPS, you can count Wolf3D, but it wasn't true 3d until Doom
Fallout - The best post apocalyptic role playing adventure game to date
Half Life - An FPS with puzzles and a ridiculous modding community that produced Counterstrike and Day of Defeat
Manhunt - Manhunt 2 is nothing compared to this ritual murder adventure game
Hitman - The best controls and storyline for any assasin game
Medieval Total War - This is what you get when you combine perfectly real time strategy like command and conquer with turn based strategy like Civilization
GTA3 - Finally an open ended game where you can just screw around without being pigeon holed into a storyline