This movie was made by the animation maestro Henry Selick, who also directed the masterpiece "The Nightmare Before Christmas" (Tim Burton only PRODUCED, people). That fact, and it's source material, a novella by Neil Gaiman, one of the darkest, and best authors currently living, means that this may not be suitable for young, young children.
However, this film oozes with creativity and invention.
Coraline isn't a perfect girl at the beginning, or arguably at the end, either. like most kids, but that makes the character that much more endearing.
With suitable messages, great animation, and an inventive story, I'd recommend this film to anyone over 6.