Here are some great games that i remember:
TOM (Commodore 16, Plus/4)
ACE (Flight SIM, Commodore Plus/4/C64)
Great Giana Sisters (AMIGA, 1987)
Populous (AMIGA, 1989)
Terminal Velocity (PC, 1995)
My first 3D game, i was breathless!!
Realms of the hounting (PC, 1996)
One of the most athmospheric and fascinating games i ever played. Unknown and underrated. Have to install and play it again on my old pc!
The Elder Scrolls: Daggerfall
The biggest gaming world i had ever seen! The dungeons were so large and complex, it gives me nightmares even today when thinking of it. And there werde thousands of them! And hundreds of cities! The size of the world of Morowind and Oblivion is just a joke compared to Daggerfall!
Unreal (Awesome graphics, but a real torture on a PI 133 Mhz with 16 MB RAM hehe! But when the game came out in 1998 i could not resist to buy it)
Unreal Tournament
Half-Life
Call of Duty
TES: Morrowind
TES: Oblivion
Far Cry
Widescreen modes would have made every old game better! Of course this was not possible because old computers often were connected to Television and the resolution was limited. For every new game. Widescreen is a big advantage! A 4:3 screen is just like wearing blinders (is that the right word? I mean these things horses have on both sides of their head to limit their FOV :) you know what i mean)