This gen

1. Dead rising
2. Gears 2
3. Gears 1
4. Halo 3
5. Condemned: Criminal origins

All time

1. Shenmue 1
2. Shenmue 2
3. Streets of rage 2
4. Guardian Heroes
5. Sonic and Knuckles

Honourable mention this gen...... Crackdown

Honourable mention all time....... Resident evil 4

Gears of war 2
Call of duty 4
Devil may cry 4
Gears of war 1
Halo 3

Boy that's a tough one. Can I remember that far back? If I do will I be looking at old games through rose tinted glasses? Anyway let me attempt a top 5

THIS GEN (including handhelds)
1. Mario Galaxy
2. Advance Wars Dual Strike
3. Brawl
4. Fallout 3
5. Twighlight Princess Zelda

Honorable mentions - Mario Kart Wii, Resident Evil 4

ALL TIME
1. Street Fighter 2 (Arcade)
2. Mario 3
3. Mario Galaxy
4. Mario 64
5. Perfect Dark

Honarable mentions - Battletoads, Advance Wars Dual Strike, Twighlight Princess, Ocarina of Time, Pikmin 2

My Top 5, This Gen:

1. LittleBigPlanet (PS3)
2. Wii Sports (Wii)
3. Pokemon Diamond/Pearl (DS)
4. Geometry Wars: Galaxies (DS)
5. Heavenly Sword (PS3)

this gen

1)MGS4
2)Bioshock
3)Uncharted
4)Gears of War
5)Super Mario Galaxy

This gen:

1 - Super Smash Bros. Brawl
2 - Super Mario Galaxy
3 - Metal Gear Solid 4
4 - Mario Kart Wii
5 - Metroid Prime 3: Corruption

All time: (This is so hard, 5 is such a small number)

1 - Starcraft
2 - Chrono Trigger
3 - Resident Evil 4
4 - Diablo II
5 - Super Smash Bros. Brawl

I didn't include RE4 in my current gen list because I played it first on GameCube and it also allowed me to squeeze in MP3.

This gen (I can't really say much because I just have a SD X360 haha):

1 - Gears of War
2 - Dead or Alive 4
3 - Halo 3
4 - Bioshock
5 - Turok

All time:

1 - Final Fantasy X
2 - Super Metroid
3 - F-Zero GX
4 - Resident Evil 4
5 - Metal Gear Solid 3

This gen
1. Lost odyssey
2. PES series
3. Fable2
4. Ace Attorney series
5. Infinite Undiscovery

All time
1. Lost odyssey
2. Chrono trigger
3. Zelda OOT
4. PES series
5. Super robot war series

TOP 5 THIS GEN

1. Dead Rising

2. Dead Space

3. Mass Effect

4. Bioshock

5. Burnout Paradise

TOP 5 ALL TIME

1. Legend Of Zelda Ocarina Of time (N64)

2. Elite (Atari ST)

3. Doom (PC)

4. Super Mario 64 (N64)

5. Resident Evil 4 (GC)

This Gen:

1. Resident Evil 4 Wii Edition
2. Super Smash Bros. Brawl
3. The Legend of Zelda Twilight Princess
4. Super Mario Galaxy
5. No More Heroes

All-Time:

1. Super Smash Bros. Melee
2. Resident Evil 4 Wii Edition
3. The Legend of Zelda Ocarina of Time
4. Tales of Symphonia
5. Jazz Jackrabbit 2