According to the ESRB, this game contains: Blood and Gore, Language, Violence
Parents don't have anything to worry about. The graphics are very artistic and abstract, not at all anything that resembles realism. There is no questionable language, and no sexual situations. The only violence in the entire game is in the final set of levels when Mr. ESC can wield a lightsaber or be blasted by aliens. Even so, there is no gore or any explicit violence. It might be extremely hard for younger ones due to the heavy slant towards logic and inductive reasoning, but there is nothing here to corrupt them.
Puzzle game fans and people who liked Abe's Oddysee should get the game immediately. It follows in the same spirit closely but ends up being a more enjoyable experience altogether because the levels come in bite-sized chunks and the difficulty has been vetted to a much higher degree.
Download fans will be thrilled to know that although the game features 100 levels out-of-the-box, Taito has plans to let players download even more. At the time of this review, there were 30 more levels available, coming in themed chunks of 10 apiece.
Deaf and Hard of Hearing gamers will have no problems. The brief cutscenes are accompanied by text, and there are no significant auditory cues. Everything is visual here, and the game is so streamlined there's no need to worry about anything besides making jumps and scoping out civilians. I played about 75% of the game without sound, and had no difficulty whatsoever.