Meet Dave (2008)

A spaceship shaped like a human lands face first on Liberty Island. Its crew (of tiny, intelligent, and unemotional beings) is looking for an orb sent from its planet to extract the oceans' salt, which will ruin Earth. The orb is in the possession of Josh, the fifth-grade son of a single mom whose car strikes the ambulatory alien spaceship and cripples its power supply. The crew has 48 hours to recover the orb, throw it in the Atlantic, and leave Earth. Over the course of two days, the ship's crew experiences chaos and emotion in New York. Do Earth's giants - Josh and his mom - have anything to teach these brainy aliens? Meanwhile, mutiny is afoot and the cops are closing in.