Shrek the Third

Plot from Flixster
Plot: When Shrek married Fiona, the last thing he had in mind was becoming the next King. But when Shrek's father-in-law, King Harold, suddenly croaks, that is exactly what he faces. Unless Shrek (with the help of his trusted companions Donkey and Puss In Boots) can find a suitable King for Far Far Away, the ogre could be stuck with the job. The most promising candidate, Fiona's cousin Artie, an underachieving Medieval high school slacker, proves to be more of a challenge than they bargained for.

My take
Just for making me laugh so loud when Donkey and Puss switched bodies. Priceless. Full of LOL moments, this one.