Shrek is a GREAT series of movies! One set the tone, two carried it forward, and the third one was good, although not near as good as teh first two. The visual effects of the movie were incredible, story lines were very cute, and the characters and voices were perfect! Good for both adult and kid, although some of the slightly "adult" humor goes over most kid's heads.
Definitely recommend the first 2. Would wait for dollar movie or DVD/VHS on the third one.