Well this is how I look at it
Rayman, Rayman Origins, Rayman Legends, Jak and Daxter: The Precursor Legacy, LittleBigPlanet and LittleBigPlanet 2 - kiddy (although I consider these to be aimed for towards children, I have no trouble getting into these I find them to be some of the funnest games.)
Ratchet & Clank (all), Rayman 3, Jak II, Jak 3 - Enjoyable for all ages. (No matter how old you are, you cant say these are too childish for you… well Maybe Ratchet & Clank: All 4 One. I HATE SUSIE!)
Portal, Rayman 2 - tame on the outside, reasonably dark on the inside (These are the games I wouldn't be giving to my kids first. I know Rayman 2 scared the crap out of me, and Portal games to have a reasonably dark tone don't you think? I'd wait until the kids were older than 5)
Uncharted - Bit 'o rough language and killing.
inFamous - pretty dark
The others - killing and lots of people saying F%^&*
Saints Row