in no particular order :

1. lost odyssey

2. elder scrolls 3 : morrowind

3. elder scrolls 4 : oblivion

4. halo

5. grandia 3

6. halo 3

7. final fantasy 8

8. final fantasy 10

9. final fantasy 11 online

10. king's quest 5

11. myst

12. legend of zelda: ocarina of time

13. legend of zelda : twilight princess

14. super mario 64

15. super mario galaxy

16. uncharted:darkes fortune

17. star wars :knights of the old republic

18. metal gear solid 4

19. disgaea 3

20. gears of war 1

21. mass effect

22. grandia 2

23. chrono cross

24. dark cloud

25. banjo kazooie

26. doom

27. resident evil :code veronica

28. gears of war 2

29. legend of dragoon

30. shadow hearts

At first i thought you meant in order!!
but since they don't have to be in any order i'll post

1. Halo 3
2. Halo 2
3. Halo
4. Gears of War 2
5. Mass Effect
6. Guitar Hero 2
7. Guitar Hero 3
8. Guitar Hero: Metallica
9.Rock Band 2
10. Guitar Hero World Tour
11. God of War
12. Fable
13. Fable 2
14. Call of Duty 4
15.Forza Motorsports
16. Forza Motorsports 2
17. The Orange Box
18. Fallout 3
19. Battlefield: Bad Company
20. Castle Crashers
21. Bioshock
22.The Lord of the Rings: Battle for Middle Earth
23. Mirrors Edge
24. Lost Odyssey
25. Dirt
26. GTA4
27. Assassins Creed
28. PGR4
29. Gears of War
30. Too Human

okay this will be in no specific order and a pretty rough list. Top 30 is a lot, its much easier for just 10. Here goes. Oh yeah, and 1 game per franchise. I'm Mostly a Playstation guy. I have a 360 and I've had Nintendo consoles but Sony is my top.

1. Gran Turismo 3

2. Crash Bandicoot 2

3. Grand Theft Auto: Vice City

4. Fallout 3

5. Elder Scrolls IV: Oblivion

6. Call of Duty 4: Modern Warfare

7. Halo: Combat Evolved

8. Assassin's Creed

9. Rainbow Six: Vegas

10. Ghost Recon Advanced Warfighter

11. No One Lives Forever

12. Ratchet & Clank

13. Need For Speed: Hot Pursuit 2

14. Uncharted: Drake's Fortune

15. Resistance: Fall of Man

16. Madden NFL 06 or 09

17. Killzone 2

18. Fight Night Round 3

19. Socom II: US Navy Seals

20. The Getaway

21. Driver 2

22. Star Wars Battlefront II

23. James Bond: Nightfire

24. The Sims

25. Roller Coaster Tycoon

26. Mario Kart

27. 2Xtreme

28. Cool Boarders 3

29. Super Mario Bros 3

30. Pokemon Red

Dude. You are REALLY into knowing everyone's favorite games, aren't you? Anyhoo, I'll make a list when I get off of work in a few hours.

in no particular order:

1. Super Mario Brothers
2. Super Mario Brothers 3
3. Metal Gear Solid 2
4. MegaMan 2 
5. FF Tactics
6. FF IX
7. Legend of Zelda
8. LoZ: Ocarina Of Time
9. LoZ: Majora's Mask
10. DKC 2: Diddy's Kong Quest
11. Sonic the Hedgehog 2
12. Chrono Trigger
13. Chrono Cross
14. Crash Bandicoot 2: Cortex Strikes Back
15. Mario Kart Wii
16. Star Fox 64
17. Suikoden II
18. Earthbound/Mother 2
19. Megaman X4
20. Super Mario 64
21. Super Mario World
22. Super Mario Galaxy
23. Super Mario Sunshine
24. LoZ: Link's Awakening
25. Loz: Wind Waker
26. FFF: Chocobo's Dungeon
27. Wii Sports
28. Xenogears
29. Megaman Legends 2
30. Pikmin 2

I apologize if there's too many Nintendo games :P

Well, in no particular order as well:

1. Deus Ex (pc)

2. Unreal Tournament (99) (pc)

3. Battlefield 1942 (pc)

4. Command & Conquer (pc)

5. Gears of War (360)

6. Metal Gear Solid (pc)

7. Ultima VIII Pagan (pc)

8. Mass Effect (360)

9. Halo 3 (360)

10. MechWarrior 2 (pc)

11. Final Fantasy Legend II (gb)

12. Bioshock (pc)

13. Fallout (pc)

14. Jet Set Radio (dc)

15. Pro Evolution Soccer series (psx/pc/360)

16. Doom (pc)

17. Quake (pc)

18. Indiana Jones and the Fate of Atlantis (pc)

19. Day of the Tentacle (pc)

20. Space Quest IV (pc)

21. Super Mario Land (gb)

22. Star Wars KOTOR (pc)

23. God of War (ps2)

24. Sonic & Knuckles (md)

25. World of Warcraft (pc)

26. Homeworld (pc)

27. Too Human (360)

28. Guilty Gear X (ps2)

29. WH40k Dawn of War 2 (pc)

30. Psychonauts (pc)

Following the format of no particular order

30 Final Fantasy VIII (PS)
29 Chrono Trigger (SNES)
28 Chrono Cross (PS)
27 Final Fantasy VI (SNES)
26 Gunstar Heroes (MD)
25 Jet Set Radio (DC)
24 Virtua Fighter 2 (Sat)
23 Virtua Fighter 4 (PS2)
22 Shining Force III (Sat)
21 Shenmue (DC)
20 Animal Crossing (GCN)
19 Rez (DC)
18 Gunvalkyrie (XB)
17 Pikmen 2 (GCN)
16 Earthbound (SNES)
15 Orange Box (X360)
14 The Typing of the Dead (DC)
13 Seaman (DC)
12 Mr Mosquito (PS2)
11 Beyond Good and Evil (GCN)
10 Patapon (PSP)
9 Alien Hominid (PS2)
8 Ryu ga Gotuko 2 (PS2)
7 Phantasy Star (MS)
6 Shining Force CD (SCD)
5 Dragon Force (Sat)
4 Sakura Taisen IV (DC)
3 Shenmue II (DC)
2 Sonic the Hedgehog 2 (MD)
1 The Legend of Zelda Windwaker (GCN)

1.Final Fantasy VII (PS1)

2.Zombies ate my neighbors (SNES)

3.Resident Evil (PS1)

4.Grand Theft Auto 2 (PC)

5.Grand Theft Auto (PC)

6.Grand Theft Auto IV (PS3, 360)

7.Grand Theft Auto: San Andreas (PS2, xbox)

8.Grand Theft Auto: Vice City (PS2)

9.Grand Theft Auto III (PS2)

10.Dead Space (PS3, 360)

11.Condemned: Criminal Origins (360)

12.Doom (PC)

13.Killzone 2 (PS3)

14.Fallout (PS3)

15.The Getaway (PS2)

16.The Getaway: Black Monday (PS2)

17.Mighty Morphin Power Rangers (SNES)

18.God of War (PS2)

19.God of War II (PS2)

20.Oddworld: Abe's exodus (PS1)

21.Mario 64 (N64)

22.Syphon Filter (PS1)

23.Assassin's Creed (PS3, 360)

24.Resistance 2 (PS3)

25.Resistance: Fall of Man (PS3)

26.Shenmue II (DC)

27.Tekken 3 (PS1)

28.Sonic the Hedgehog (Genesis)

29.007: Nightfire (Xbox)

30.Valkyrie Chronicles (PS3)

1. Grandia II
2. Shining Force II
3. Shining Force I
4. Final Fantasy IX
5. Final Fantasy VII
6. Shadow Hearts: Convenant
7. Shadow Hearts
8. Tales of Phantasia
9. Shining Force III
10. Resident Evil 4
11. Golden Sun
12. Golden Sun II
13. Sonic Unleashed
14. Valkyria Chronicles
15. Dragon Force
16. Shining Force CD
17. Sonic and Knuckles
18. Sonic 3
19. Fear
20. Bioshock
21. Silent Hill
22. Chrono Cross
23. Septerra Core
24. Bahamut Lagoon
25. Ogre Battle 64
26. Legend of Zelda: Majora's Mask
27. Shining Force: Final Conflict
28. Growlanser: Generations
29. Tales of Rebirth
30. Xenosaga: Episode 1

I made a top 50 games with friends for the end of the year, so here are my top 30 as of December 31, 2008:

30. StarCraft/BroodWar (PC)
29. StarFox 64 (N64)
28. Super Mario Sunshine (GCN)
27. Pokemon Silver (GB)
26. Diddy Kong Racing (N64)
25. Fire Emblem: Radiant Dawn (Wii)
24. Super Smash Bros. (N64)
23. TimeSplitters: Future Perfect (GCN)
22. Pokemon Red (GB)
21. Paper Mario: The Thousand Year Door (GCN)
20. Super Smash Bros. Melee (GCN)
19. Metroid Prime 3: Corruption (Wii)
18. Banjo-Tooie (N64)
17. Super Smash Bros. Brawl (Wii)
16. Okami (Wii)
15. The Legend of Zelda: Twilight Princess (Wii)
14. Conker's Bad Fur Day (N64)
13. Mario Kart 64 (N64)
12. WarCraft III: Reign of Chaos/The Frozen Throne (PC)
11. Sonic the Hedgehog 3 (Genesis)
10. Resident Evil 4/Wii Edition (GC/Wii)
9. Super Mario 64 (N64)
8. The Legend of Zelda: The Wind Waker (GCN)
7. Banjo-Kazooie (N64)
6. Super Mario World (SNES)
5. Sonic the Hedgehog 2 (Genesis)
4. Metroid Prime (GCN)
3. The Legend of Zelda: Ocarina of Time (N64)
2. Super Mario Galaxy (Wii)
1. Sonic & Knuckles (Genesis)