According to ESRB, this game contains: Violence
Parents will note that the game has gotten a T rating for violence. This is armed conflict, so there's naturally a whole lot of shooting the "bad guys." That might be reason enough to keep it away from Little Timmy, but a better reason is because he just won't have that much fun playing it. This is a game for older players and is relatively involved. Most kids won't find anything in it other than frustration.
Casual gamers may also be put off by the complexity of the experience. Running and gunning is a good way to die in Ghost Recon 2. Using some strategy and mastering the interface is essential in some of the later missions. If a player isn't committed to doing these things, this game will beat them down regularly.
SOCOM II fans will want to give the Xbox version a look (skip the PlayStation 2 version; it's a different, and by all accounts, inferior game). I'm not a rabid SOCOM II player, so I can't get into the minutiae of why one is better than the other, but I can tell you that I enjoyed both titles. I don't think Tom Clancy's Ghost Recon 2 is better, but the two games have a lot of good things in common.
Deaf and Hard of Hearing gamers will be pleased to know that there is an option for subtitles.