First, the easy bit. This film is brilliant. Funny, fast-paced, ironical - people have talked about Wall-E or Up being among the major films of their years, but to my mind, this is the big-time computer animation that really has a claim for that sort of standing; notably, when it tries to be moving, it usually does so without being too blatantly manipulative.
However, it also left me glad that I don't have children, because that means that I didn't have to try and explain this film to them. Aside from the fact that the whole thing is about maturity and loss and the prospect of death, there are the three-eyed green blobs with their religious obsessions and eventual apotheosis, or Buzz's Spanish alternate persona and its curious appeal for Jessie. One also imagines generations of children growing up into their first encounters with the prison movie and PoW film genres, and suddenly realising what much of this thing was all about - and that's not just the minor cliches, it's also big-ish things about the corruptions of petty power. The film's direction also repeatedly employs the semantics of the horror genre, with the blank-eyed zombie Big Baby and the culminating plunge towards a hellish pit. And, of course, there's Ken, concerning whom one might choose to explain subtle concepts like metrosexuality and '70s disco fashion to the sprogs, if one wanted to get more complicated than just saying that he's evidently gay. All this is much of the point of the movie, mind, and I think that it's in more danger of befuddling kids than of seriously traumatising them, but it really does feel like a film about a box full of toys, written for a non-child audience - something that may confuse some parents as well as their offspring.
I saw it in 3-D, incidentally, and that proved unintrusive without being at all necessary in this case. Which I guess could be taken as the sign of maturity in the technology, or just money wasted.