According to ESRB, this game contains: Blood and Gore, Intense Violence, Language

Parents should be cautious of some mild blood and gore, but there's nothing overtly graphic here, nor is there any over-the-top language
Fans of Half-Life 2 should pick this up to get a little more of their Half-Life fix. Just don't expect anything really new.
Shooter fans may find this is worth picking up, only because it's been a rather dry year for the genre. I highly recommend the free Half-Life 2: Rock 24 mod that is downloadable for free for owners of Half-Life 2. It's a user mod that has Freeman escaping a Combine prison, and it provides a good romp without the premium that Valve is asking for Episode 1.
Everyone else may want to pass on this one, particularly if Half-Life 2 wasn't your style. There's nothing here that wasn't in Half-Life 2, so it's not going to win any new converts. If you are one of the unlucky gamers who hasn't played the original Half-Life 2, the original is definitely worth a purchase as it can be had for around $20.
Deaf and Hard of Hearing gamers will miss out on a substantial number of audio cues and dialogue; while audio isn't necessary to play the game, it can make a significant difference in its playability.