Doom

Half-Life

Half-Life 2

Metroid Prime

Metroid Prime 2

Metroid Prime 3

CoD4

1. Killzone 2

2. Deus Ex

3. Doom 2

4. Doom 3

5. Doom

6. Call of Duty 4

7. Dead Space

8. Far Cry

9. Quake

10. Duke Nukem 3D

Because it actually has a really balanced, well done multiplayer mode with bots, difficulty tiers and the like.  Keep in mind I am very much a ps2 fan from last gen, and there was no ps2 FPS that was the "total package" as much as Killzone.  maybe Timesplitters, byt it was better on the gamecube.

Also, I can't stand Halo games

first of all, metroid prime is not a fps.

1. halo 1

2. turok 2 seeds of evil

3. half-life 2

4. Duke nukem zero hour

5. bioshock

6. call of duty 4 modern warfare

7. call of duty world at war

8. modern warfare 2

9. bf bad company 2

10. halo 3 odst

Return to Castle Wolfenstein
Jedi Knight
Jedi Knight Outcast
Dark Forces
Heretic
S.T.A.L.K.E.R.
Bioshock

Only those come to mind at the moment.