According to ESRB, this game contains: Absolutely nothing objectionable.
Parents should be absolutely fine with their children playing this game. While too hard for younger children, it's a straight driving game with no objectionable material of any kind.
Car Fanatics will look upon this game as the holy book of their religion. It has all the cars and accessories they dream about at night, and if the ad copy is to be believed, it's the next best thing to actually owning the vehicles.
Deaf and Hard of Hearing gamers should have no trouble at all. There are no significant audio cues in the game, and there is plenty of text explaining all the races, cars, and tuning options.