Don't dismiss The Spongebob Squarepants Movie as "just a kids' movie", although that's exactly what it is.
I imagine there are probably people about the place who haven't been into the Spongebob world - follow the link if not, it gives you an excellent grounding in the basics. OK, I lied, that link is pretty much Nickelodeon hideosity.
It is the usual kid cartoon world of wacky, lovable creatures - OR IS IT? Watch more than a couple of episodes and you'll see some real weirdness creep in. Witness Spongebob's pet snail, called Gary, who meows, and his friend Sandy, a squirrel who must live in a diving-suit in order to breathe underwater. These are just the regular characters.
So, this movie has the titular 13-foot Hasselhof (watch the DVD extras to find out about that one), Scarlett Johanssonsensonsun, a massive rock'n'roll finale with crossdressing, and a proper moral. What more could one want?
Watch out for this though.