I just got back from Wall-E, and I enjoyed it.
The first half of the movie takes place on a North America covered in garbage...which it is Wall-E's task to clean up. (Other Wall-E's have fallen by the wayside, he alone remains.) (Small children may constantly barrage parents with questions for the first 10 minutes of the movie, as it shows Wall-E cleaning up garbage...left behind by people who shopped huge conglomerate stores called Buy 'N Large.)
A probe ship lands and deposits Eve, a cool, slick, flying robot that Wall-E falls in love with. Wall-e had found a plant...which he shows to Eve. She puts it in her interior compartment and immediately goes dormant, sending out a signal to the probe to come and get her. (Trying to see if photosynthesis is occurring on earth is her purpose.)
Wall-e follows her onto the ship, which takes them to a huge Buy N Large spaceliner which left earth 700 years ago, now full of thousands of large, chair-bound, computer watching people... but all is not what it seems there...
Lots of good messages here, but one irony. As you went into the theater - at least at my theater - every child was handed a Wall-e watch by the movie clerk. A plastic, blue, ugly thing, which little children will probably love... but the battery isn't replaceable so it's what's called a Planned Obsolescent object. And while I intend to save mine in my movie memorabilia collection (yes, the clerk gave me one even though 'm 45) most kids will throw them straight into the garbage as soon as they stop working...if not sooner!