Trivia:
The scene where Princess Fiona burps was not originally included, and was written only after Camelon Diaz burped after drinking some coke during a recording session.
Goofs:
Continuity: As Shrek and Donkey are leaving we see them walk through sunflowers before the onions and cabbages. Later as they are walking back, the sunflowers are farther away from the castle than any other plant.