Well KZ2 to me is very very under-rated, but to each his own.

350 hours I agree is bad, and I don't play much games anymore, but lol there's guys who have invested over 2500 hours into it :)

I've invested half an eternity in Starcraft, Rome: Total War and Medieval: Total War.

I've invested an eternity and a half in Perfect Dark.

Counter-strike: Source - 2000 hours :p

invested is not a good word. i prefer "wasted." 

I've wasted most of my time on lost planet 1 and gears of war 1. 

Guild Wars: 832 hours
SSBB: 252 Hours
LoL: 700 Hours
DII LoD: well over 1500 hours
Q3: 1000 hours
WoW: 450 or so hours

Battlefield: Bad Company 2

254h 54m

Rome: Total War (not including the time I played the game when I first pirated it)

According to Steam: 326 Hours

No info on Medieval II, but probably at least 200 hours.

Super Smash Bros. Brawl -  1211 hours

Monster Hunter Tri - 244 hours

Halo 3 - 170 hours

Pokemon Pearl - 150 hours

Dragon Quest VIII - 108 hours

Tales of Symphonia - 102 hours

1 WoW (about 200 days)

2 Counter strike about 2-3K hours)

3 Zelda (the first) about 1000 hours

4 Warcraft 3 probably arround 400-500 hours

5 Golden Eye 300-400 hours

6 Diablo 2 Like 200 hours... my disc overheated and broke :x

7 Mechwarior 4 Like 150 hours

All FFs 80-100 hours

Mario karts... I have no freken idea, but the SNES and Wii ones are in the top 10.

there are many games in the 30-60 range (many RPGs)

oh forgot CIV... it takes me about 40 hours per run so....400? (3&4)

- Demon's Souls ----- 350 hours

- Final Fantasy XII ----- 130 hours

- Resident Evil 5 ----- 110 hours

FFXII - about 200 hours.

FFX - about 90 hours.

Oblivion - about 80 hours.

Can't remember the rest.