They are legal to use because all it does is get rid of the need for the CD. You can get one at gamecopyworld.com
Mods, if this is against the rules, then please tell me. But its not pirating or anything.
Actually, the use of cracked EXE's even with legally purchased games is still a bit of a grey area. As much as DRM sucks, it's especially blurry if you're using it to remove that DRM (requiring a CD to be in the drive is one of the earliest forms of DRM by the way, before some halfwit decided it'd be a great idea to actually write a program that would screw up games for both honest and dishonest gamers).
I wouldn't recommend to someone to do it, but if they came up with it on their own anyway then it's their choice.
Actually i read for people in the usa that its legal to do this if it is the only way for it to run on your pc. i read this on the dmca info page on the .gov site (dont remember if it was for the justice or congress.
I can read that. But Windows related knowledge is good for other people who are in this situation that are using Windows.
And, just a thought, but could you not make a copy of the disc? If I remember correctly the disc is ~5.5GB of information, so a dual layer dvd would do that trick. If you don't have one, you could always make a disc image of it, and use DTLite or some other disc image software to read the disc.