This is a strangely magical movie about the power of imagination and... Science?
From the start, everything seems a bit off, yet intriguing and quite captivating. And luckily, it remains so for the entire duration. Characters speak in strange manners and repeat non-sensical points (e.g. "Trust in Antiquity!"). Wizards get ulcers, knights get hammered and preach about chivalry, and dragons can have heart attacks. Chinese stereotype wizards are also okay, because someone had to represent the realm of "peace and tranquility", as "land", "sea", and "death" were already taken. New plot points and side-stories are introduced and elaborated throughout - often through flashbacks. Or, through a sudden meta-layer in which the main character is a present-day science geek, and actually the author of the book which becomes (it's not finished) the basis for the film, while playing a boardgame with all the characters previously introduced. And, of course, the final evil wizard (voiced by James Earl "Vader" Jones) is defeated in a showdown of his magic power versus science.
Peter wins by charging headfirst with an outpour off everything from Newton's Laws to molecular mass, before moving to the K.O. with an alphabetical namedrop of theories and fields from Algebra to Zoology. Death follows, as no evil wizard with seven dragon heads, a fiery sky and earthquakes can bear such pretensions.
And still, for all it's weirdness and sloppy animation, it's a pretty cool and endearing movie with a fun story filled with awesome adventure (it feels like a game of D&D), great voice work and a fantastic score.
It's also one of the few "children's movie" with decent morals and cynicism, preaching about the value of "science", while using "advanced film techniques". Basically, like Ratatouille did with creativity and art.
8/10 - Too bad it's probably too strange, and a little scary, for the youngest in the crowd.