It's not 25 but i did put a top 20 gallery image together of my favorite games recently in another discussion group.
1. Max Payne (2001)
2. Half-Life 2 (2004)
3. Bioshock (2007)
4. Jedi Knight 2: Jedi Outcast (2002)
5. Uncharted 2: Among Thieves (2009)
6. Batman: Arkham City (2011)
7. Red Dead Redemption (2010)
8. L.A. Noire (2011)
9. Alan Wake (2010)
10. Portal 2 (2011)
11. Deus Ex: Human Revolution (2011)
12. The Chronicles of Riddick: Escape from Butcher Bay (2004)
13. DooM 2 (1994)
14. Quake (1996)
15. Command and Conquer (1995)
16. Jazz Jackrabbit (1994)
17. Dark Forces (1995)
18. Wolfenstein 3D (1992)
19. SiN (1998)
20. Rise of the Triad: Dark War (1994)