Sid and Marty Krofft couldn't have imagined their family fantasy show being used to make sexual innuendo and slyly drop F-bombs in a PG-13 movie. Any innocence from their original Land of the Lost is gone in the Will Ferrell comedy version, but this time it works. Perhaps Ferrell has learned his lessons from Bewitched and figured out how to bring his brand of comedy to a magical classic.
Ferrell's Rick Marshall is a typical Will Ferrell character, just successful enough to be dangerous. When his theories on tachyons and time travel are discredited, he's reduced to teaching middle-school science, until Cambridge scientist Holly Cantrell (Anna Friel) brings him evidence to prove his crackpot ideas. His tachyon meter sends Marshall, Holly and trailer-park carnival proprietor Will Stanton (Danny McBride) to the land of dinosaurs and Sleestaks.
Land of the Lost doesn't have anything to add to the fantasy/sci-fi genre. You're not going to find any compelling time-travel theory or wormhole analysis. It is simply a device, a MacGuffin, as George Lucas or Alfred Hitchcock would call it, to get modern-day characters to react with real-world irreverence.
We've really never seen that before. As funny as Jeff Goldblum's intellectual one-liners were in the Jurassic Park movies, we've never gotten to see real people just freak the hell out in a fantasy world like this. Real people wouldn't keep it PG with a dinosaur on their tail. Real people would mouth "F you" to Chaka.
The film really sets up the comedy, because the action is not much compared to really hardcore adventure fantasy. In 2009, just running from a dinosaur or swinging from vines isn't that suspenseful. Making off-color remarks while doing it is pretty freaking funny, though.
Should parents take their kids to see Land of the Lost? Well, the cool ones should. If you think your kids haven't heard you say f--k, or if you're worried that Chaka's groping of Holly will inspire copycat molestation, by all means shelter your children from this scathingly subversive comedy.