Just a couple notes from an engineer's point of view about this movie and its inaccuracies:

The year is around 3000 A.D. and the cave-dwelling humans come across some vintage 20th century stuff, specifically a jet-fighter and a nuclear bomb.

I'm not sure about the internal components of a jet-fighter, or whether one would still work after a thousand years, but I am sure that the jet fuel wouldn't. JP-5 jet fuel has a shelf life of around 4 years. In fact, most petroleum by-products are inherently unstable. Try starting up a lawnmower after it's been sitting for a year with gasoline in the tank...it's not much fun. There's no way that 1000 years from now those fighters would have taken off, unless the primitive humans had somehow set up their own petroleum distillation plant.

Modern nuclear weapons use tritium in their design. The tritium is an essential part of the bomb, acting as an accelerant to the nuclear chain reaction. Unfortunately tritium has a half life of aprroximately 12 or 13 years, which means that militaries must constantly replace the tritium in their bombs. The only current manufacturer of tritium in the U.S. is the Savannah River Site, a nuclear facility located near the Savannah River in eastern Georgia.

After 1000 years the tritium will have decayed to basically 99% ordinary Hydrogen gas, which would make it pretty damned impossible for the bomb to go off, like it did in the movie.