1. Grand Theft Auto: San Andreas
Best game ever. Period.
2. Metal Gear Solid 4: Guns of the Patriots
If you have a PS3, and you don't have this, you need to take a look at what you're doing with your life. If you don't have a PS3, then you need to take a look at what you're doing with your life.
3. Grand Theft Auto IV
Sure, not as good as the other GTA games. Sure, the friend system is annoying. But there's no better game to do random shit in.
4. Fallout 3
Get the PC version, if you can. Download some mods like FOOK and FWE, and the game becomes 100X better.
5. The Elder Scrolls IV: Oblivion
Same story as Fallout 3.
This game is just too cool. For words.
7. Indigo Prophecy
One of the best games I've ever played, until the last couple hours. Even the lead dev admitted he went crazy. But it's worth it; no other games lke it (except the upcoming Heavy Rain).
8. Saints Row 2
Just DON'T buy the PC version.
9. Uncharted 2: Among Thieves
Go look up a video, if you need an excuse to play it.
10. Brütal Legend
Dude. Jack Black. Shitty? Yeah. Jack Black? Yeah.
11. Dragon Age: Origins
Made by Bioware. That should tell you everything right there.
12. Madden NFL 10
Football is the only true sport.
13. Fight Night Round 4
Boxing is the only other true sport.
14. UFC 2009 Undisputed
Except MMA, of course.
15. True Crime: Streets of LA
Is this game good?
Is this game bad?
This game recreates all of L.A., however, so it makes it on this list.
Also, it has snoop dogg as an unlockable character.
If I need to say more, than just leave.
16. Half-Life 2
If you don't have this, you are a freak.
17. DiRT 2
Codemasters make them some good racing games.
Horror game; actually scary, actually fun to play.
19. Big Rigs: Over the Road Racing
I take that back about GTA San andreas being the best game. This, without a doubt, is pure genius.