I almost put that one on my list. Though decision...
I like your top 10. Nicely commented too :)

Thanks! I usually get comments like, "WHERE'S HALF-LIFE 2 AND COUNTER-STRIKE?!".

uurg... top 10?? so many games I love... but here's a list of MY top 10 games of all times. i.e. games I played way too much and have nostalgic memories of (there might be 12, oops):
Dune 2 (I also love C&C, but Dune 2 gave birth to C&C and slapped its bum to make it cry)
System Shock 2 (replaying it right now)
Deus Ex
Baldur's Gate 2
Morrowind
Rogue (spent way too many countless hours on the most complex/simplest of games, but its still awesome)
Starcontrol 2 (This one might be my all time time waster, no one mentioned it yet!?!)
Lands of Lore Series
Space Quest 3 & 4 (I guess I could just say SIERRA GAMES)
Mechwarrior series
Battlefield 1942
Freespace 1 & 2
Battlezone 1&2 (thanks spitfire, almost forgot)
Grim Fandango

Again, in no particular order :
Baldur's Gate Trilogy
Neverwinter Nights ( PW Multiplayer )
Il-2 Sturmovik Series
Jane's AH-64D Longbow
PlaneScape Torment
Mechwarrior II & Mercenaries
GalCiv II
Morrowind
Eve Online
TIE Fighter Collector's Edtition

1 Beyond Good & Evil
2 Star Wars Racer
3 Half Life : Opposing Force
4 Duke Nukem 3D
5 Gunman Chronicles
6 The nomad Soul : Omikron
7 Soldier of Fortune
8 Dungeon Keeper 2
9 Star Wars Rogue Squadron
10 SimCity 3000

Fixed positions
---------------
1 Riven (closest thing i've seen to a perfect game)
2 Myst / Real Myst
3 URU CC
4 Myst IV Revelation
5 Myst III Exile
6 Myst V End of Ages
Interchangeable
---------------
-Black Dahlia
-Amber: Journeys Beyond
-T L J
-Lighthouse
-Dark Fall: The Journal (Jonathan Boakes = Good Games)
-Obsidian
In case anybody is wondering my top 20 is entirely made of Adventures.
21 - Half Life...i guess.

Greatest games that I have played -
1. Deus Ex
2. Medieval Total War: Viking Invasion
3. Operation Flashpoint
4. Morrowind
5. GTA4
6. Mafia
7. Empire Total War
8. Baldurs Gate 2
9. Fallout 3

1. Half-Life
2. Operation Flashpoint
3. Fallout
4. Metal Gear Solid
5. Super Mario Brothers (any of them, but I prefer 3)
6. Team Fortress Classic
7. Mafia
8. Red Faction (none of that Guerilla shit, thank you)
9. World in Conflict (awesome game in every way)
10. Call of Duty (the first one, duh)

Top 10 huh?
I don't think I can really list my top 10 in any order, it's like me trying to classify my top five favorite bands. I love different ones for different reasons.
Fallout series (2/1/tactics/3 in that order)
Diablo series.
Troika's games.
Star Craft
Age of Mythology
Warlords Battlecry III
Sacred series
FFVII
City of Heroes/Villains
Warhammer 40K: Dawn of War. Specifically the Dark Crusade and SoulStorm expansions.
And there's still more games I know I've loved, and I don't know if I should put them on while removing another.. Like Titan Quest, Silverfall, Portal, Audio Surf, etc.

All of these plus Gothic 3 and Monster Madness.

I can come up with 5 pretty easy but not sure about the next 5 spots.
Doom II
Super Metroid
Super Castlevania IV
Diablo
Unreal Tournament
Diablo II - LoD
Castlevania - The symphony of the Night
-
-
Dawn of War
I gave DoW a well deserved tenth as my favorite modern game.
I'd Give Oblivion a spot here too but the character advancement system is too broken to just sit down and enjoy the game without your char breaking down into a useless gimp.

In no particular order:
Descent (1 & 3 mainly, but I like the whole series)
Homeworld (& Homeworld: Cataclysm, I haven't played Homeworld 2)
NFS: Porsche Unleashed (One of the best arcade racers of all time)
Sins of a Solar Empire (Just got this one a few days ago, It's alot like a newer version of Homeworld)
Centipede (Amazing, but I never could beat it)
Contra (From the Nintendo NES, another one I couldn't beat)
The Adventures of Kirby (Also from the NES)
Final Fantasy (The original, that being the only one I've ever played. It was on the NES)
Jet Moto (From the original Playstation)
Burnout 3: Takedown (For the PS2)
I'm sure there are others that I'm going to remember laying in bed tonight, and kick myself for not putting them on here :-)
BTW, Is it just me, or is Descent 1 impossible on Insane? Maybe I'm just not that good, but with the keyboard it seems pretty much impossible.
Yep, knew I would forget one :-)
Another is Sonic and Knuckles Collection for PC. Amazing game!!
And yet another I forgot: StarCraft!

I guess my list would look like this right now. Most of it will probably change if asked again some other time though.
1.The Curse of the Monkey Island
2.Broken Sword 2
3.Crash Team Racing
4.King's Bounty: The Legend
5.Vampire the Masquerade Bloodlines
6.Halo
7.Europa 1400 the guild
8.The Witcher (enhanced)
9.Painkiller
10.Crusader Kings

System shock 2
Deus Ex
Knights of the old Republic
Mafia
American Mcgee's Alice
Neverwinter Nights & Hordes Underdark
Tomb Raider 1-5
F1 Challenge 99-02
Zelda: Ocarina of time (Nintendo 64)
Wonder Boy III: The Dragon's Trap (Master System)

In no particular order:
Zelda: Ocarina of time (N64)
Perfect Dark (N64)
Goldeneye 007 (N64)
Quake
Painkiller
The Punisher
Wonder Boy in Monster World (Mega Drive)
Duke Nukem Zero Hour (N64)
Sonic 3 & Knuckles (Mega Drive)
Star Wars Shadows of the Empire (N64) only thing I liked to do with Star Wars