Absolutely love this idea, I've been looking for a guide like this for years. Here's my contribution, will add more later (sorry for the shitty formatting, pulled from Excel):
Bayonetta 10
Half Life 2 Episode 1 4
Call of Duty: Modern Warfare 2 6
Half Life 2 Episode 2 6
Amnesia: The Dark Descent 8
Call of Duty 4 8
Half Life 8
Half Life 2 8
Halo 3 10
Bioshock 12
Crysis 14
Metal Gear Solid 3 (I've played this one a lot, this is with skipping cutscenes, zipping through the game, etc. First playthrough ~15)
Metal Gear Solid 2 15 (first playthrough, but I've speedrun'ed it in 2:02
Mass Effect 16 (rushed through it)
Mass Effect 2 32 (all sidequests, DLC)
Fallout 3 50 (All quests, no DLC)
The Legend of Zelda: Twilight Princess 50
Final Fantasy X 55
Final Fantasy VI 35
Final Fantasy VII 55
Dragon Age: Origins 75 (All quests, no DLC, hard difficulty, not counting restarts)
The Elder Scrolls: Oblivion 110 (all quests, no DLC)
Persona 4 120 (near complete compendium without guide; a lot of trial & error demon fusion)
Persona 3 vanilla 125 (near complete compendium without guide; a lot of trial & error demon fusion)
Metro 2033 10
Resident Evil 3
Resident Evil 2 3
Resident Evil 5 15
Resident Evil: Code Veronica 8
Shin Megami Tensei 30
SMT: Nocturne 90 (neutral path, all kalpas of Amala)
SMT: Raidou
26
Etrian Odyssey 80?
Super Mario Galaxy 30 (120 stars)
Fire Emblem: Path of Radiance 45
No More Heroes 15
Dead Space 12
Crackdown 15
Silent Hill 8
Xenogears 70
Chrono Trigger 20
Chrono Cross 30