You guys are missing the point.
Let's say 5 years from now Valve dies for whatever reason, and steam goes with it. Now say a year after that I decide I want to play some HL2. However, I don't have the files backed up, and since steam is dead I can't download it again.
In this situation...
Option 3 or 4 most likely. I guess 3 since CS is already on the xbox.
In a very recent thread, the gamespot interview maybe Doug said there would be no official Deathmatch OR Co-op. I would assume that applies to xbox as well because if they were going to make DM or Co-op for xbox they...
Please don't spam.
And I never found the trip mines too useful in single player, though I've seen them put to good use in multiplayer. Sachels on the other hand were good for sp because the ai ignored them, but had limited uses in mp.
You should search first. I know I would, because I wouldn't want to look like an idiot after 15 other people had already started topics on the same thing.