Come with me....

only big one I can think of that I haven't REALLY played a lot, despite owning all variations in the past, is Kingdom Hearts and then the Call of Duty series. like I think I once picked up a controller at someone's house and played some of the zombie mod with friends on Call of Duty, but on my own never before

  note: also Fatal Frame series, never got into that, or Persona

I didn't have a PS2 (or Xbox) until very late and so I missed out on Silent Hill, although I have friends who really like the games, so I might check it out sometime. As for Tekken, I was always a Street Fighter kid, and all my friends played Street Fighter. I might check out the series when Tekken 7 comes out though.

That's ok, i'm the worst one, i missed Final Fantasy 7, but i played Final Fantasy 8 1st time. xD

God of War
Call of Duty
Battlefield
Street Fighter
Metal Gear Solid
Gears of War

Metroid, GT, Metal Gear, Kingdom Hearts, Fallout, Street Fighter, Bioshock, may think of more

Call of Duty.

Damn right!

Every Xbox exclusive franchise, a lot of Sony exclusive franchises, Metroid and Call of Duty.

That I can think of:
Dragon Quest
Silent Hill
Monster Hunter (outside of a tiny amount of a demo)
Persona
Tekken
Dragon Age

That's about all I can think of. I've played most popular ones at least a little bit.