Here is a look at the top 3 sellers by genre according to VGC numbers.  Bundle titles are included though some games were obviously bndled much longer than others.  Some titles with big sales do not have a listed genre such as the Brain Age series. 

Action:
PS2 - Grand Theft Auto: San Andreas - 17.75 million
PS2 - Grand Theft Auto: Vice City - 14.2 million
PS2 - Grand Theft Auto III - 11.6 million

Adventure:
PC - Myst - 7.79 million
N64 - The Legend of Zelda: Ocarina of Time - 7.6 million
NES - The Legend of Zelda - 6.51 million

Fighter:
Wii - Super Smash Brothers Brawl - 8.38 million
GC - Super Smash Brothers Melee - 7.08 million
PS - Tekken 3 - 6.91 million

First Person Shooter:
X360 - Halo 3 - 9.16 million
Xbox - Halo 2 - 8.46 million
N64 - Goldeneye - 8.09 million

Platform:
NES - Super Mario Brothers - 40.24 million
SNES - Super Mario World - 20.61 million
GB - Super Mario Land - 18.14 million

Puzzle:
GB - Tetris - 30.26 million
NES - Tetris - 5.58 million
GB - Dr. Mario - 5.34 million

Racing:
PS2 - Gran Turismo 3: A-Spec - 14.87 million
Wii - Mario Kart Wii - 14.81 million
DS - Mario Kart DS - 14.24 million

Role Playing Game:
GB - Pokemon Red/Green/Blue - 31.38 million
GB - Pokemon Gold/Silver - 23.11 million
DS - Pokemon Diamond/Pearl - 16.71 million

Shooter:
NES - Duck Hunt - 28.31 million
X360 - Gears of War - 5.88 million
X360 - Gears of War 2 - 4.65 million

Simulation:
DS - Nintendogs - 21.95 million
PC - The Sims - 16.08 million
DS - Animal Crossing: Wild World - 10.57 million

Sports:
Wii - Wii Sports - 43.36 million
Wii - Wii Fit - 16.63 million
Wii - Mario and Sonic at the Olympic Games - 6.9 million

Strategy:
N64 - Pokemon Stadium - 5.88 million
PC - Theme Hospital - 3.99 million
PC - Command and Conquer: Tiberian Sun - 3.07 million

Other:
Wii - Wii Play - 22.26 million
Wii - Mario party 8 - 6.35 million
DS - Big Brain Academy - 6.05 million

Sales Scoring: 3 points for 1st place, 2 points for second place, 1 point for 3rd place.

1. Wii - 16 points
2. GB - 10 points
3. NES - 9 points
3. PS2 - 9 points
5. DS - 7 points
5. PC - 7 points
7. X360 - 6 points
8. N64 - 5 points
9. GC - 2 points.
9. SNES - 2 points
9. Xbox - 2 points
12. PS - 1 point

Most significant console with no listings:
GBA - 80 million units sold and 4th is the best placement for any game (RPG).
PSP - 45 million units sold and 5th is the best placement for any game (action).
Gen - 30 million units sold and 17th is the best placement for any game (platformer).
PS3 - 21 million units sold and 4th is the best placement for any game (action).

This is just an arbitrary sales thread created for the fun of it.  If you want me to compile a version without significant bundles, just recent consoles or no handhelds, I'll add that later....or you can do it yourself if you like.

Remember, this is only based on the figures that VGC has available.

EDIT: GTA issue fixed.

Nintendomination

Duckhunt made me lol

Wow, Pokemon dominates RPGs...

Before the month is out it shall be

1. Wii - 17 points

2. GB - 9 points

2. NES - 9 points
2. DS - 9 points

5. PS2 - 7 points
5. PC - 7 points
7. X360 - 6 points
8. N64 - 5 points
9. GC - 2 points.
9. SNES - 2 points
9. Xbox - 2 points
12. PS - 1 point

As both DS and Wii Mario Karts outsell GT3, and NSMB outsell SML

Edit - fixed for the OP fix

I understand that it's because VGC has no data, but Strategy is not really accurate since we all know Starcraft has sold much more than Pokemon Stadium (wiki puts it at 9.5 mil)

And I submitted a change for San Andreas, it's ridiculous to have it in Adventure

Good points, even when Nintendo was in last place they sold hell of a lot of software.

@Viper

why put Vice city up there and not San andreas

didn't San andeas sold more than vice city for ps2?

Why didn't you read my whole post?

A lot of inconsistencies there due to vgchartz lack of data. Especially in regards to pc games.