Global Thermonuclear War and One in the Chamber are both game types that are in MW2 but for some reason were locked from the public.

The Torrented MW2 won't give you these modes its the Alternative server that has unlocked them for there players.

I own MW2 legally, but have found that the steam version generally SUCKS. Hackers everywhere and no way to get rid of them so I copied my MW2 folder and gave one of these alternative servers a try and it is alot better then the steam version

These other servers not only give you game types that are locked in the Steam one but they also give you a server browser (not really a server browser but a host browser to find ideal host to connect to) and also have the ability to kick and ban hackers. Not only that but they allow Modded game types, such as iSnipe which is all quick scoping, Roll the Dice, random perks and special abilities and even Gun Game mods exist. Technically you can play these on Steam but Steam will VAC ban you for loading the mods and hosting them. Its no secret that MW2 for PC is absolute fail but these alternative providers have really done well to give players some power back