I had used computer since I was 7 years old, so I know about some old games which run on MS-DOS. I also played DOOM, but I loved the adventure game which called
"Little Big Adventure" 
(Other name is "Relentless: Twinsen's Adventure") at that time.
About FPS game, how about Hidden & Dangerous 2? I don't affirm the World War 2, but this game is very realistic.
My Collection:
Final Fantasy 8 for Windows
Myst URU
Sid Meier's Alpha Centauri
Thief GOLD
Thief2 The Metal Age
Thief Deadly Shadow
Completed and sold:
Grand Theft Auto 3
Grand Theft Auto:Vice City
Tachyon:The Fringe
Unreal
Unreal Tournament 2003
Quake 2
and more...
14-Dec-2006
14-Dec-2006