Just some answers:
1. Steam & retail exactly the same, buying the DVD version just aves your DL limit.
2. You can install Steam games on as many of your PCs as you want. There are even games that have Steam Cloud, holding all your settings and save games online so you don't even need to transfer those (L4D2).
3. A VAC ban will, from my research, only ban you from the actual game so you won't lose the rest of your Steam games... this is not definite but I am pretty sure.
I used it all last night with no errors/bans/spankings from VAC (although I bloody tried the SP and I get a crash every 20 mins or so Grrrrrr; nothing to do with the fixer, the SP is just unstable on my PC... the only thing)
1. There is no download limits on steam, I could download and delete a game 50 times a week and I would be fine :D That's why steam is the digital download platform of my choice.
2. Yep; so you can install the game on as many PC's as you want, you just have to log into the steam account that has a copy of that game on it.
3. The only games to use VAC aside from MW2 AFAIK are valves games. If you get banned in a Source game, you're banned in all source games. If you get banned in a GoldSrc game you're banned in all goldsrc games. Judging from that you probably wont get your other games banned but still, that banned MW2 will forever be on your account and your profile will say "VAC bans on record"
why did iw have to be such a bunch of donkeys?
I was wondering this maybe dopefish can provide some insight.
Why do they have a separate cvar for aspect ratio? Can't they just divide the aspect ratio to get it, and then it would always be correct and one less thing for users to fuck around with? And do you have any idea on how the math might look for the fov function?