Wasn't bad...
Your movie has a lot of good things about it and a lot of things that need to be worked on. It's not bad at all, but needs some work.
Lets start off with the good.
I liked the story. Cliche, but nothing terrible. I like the characters too, who had good voice actors. This aspect of the movie had nothing wrong with it.
Now we can move on to some things you need to practice.
The most obvious thing would be artwork. Right now it's too simple. Simple can work, but still it's simple. Clean it up a bit. You can still have the same style, but clean up using the brush tool a bit. Make them more definable, not just a pallette swap on the same general body. All the characters except the evil principle and the D-named guy looked alike in basic form. Nothing wrong with this, but just clean it up and make them more distingushiable(sp???)
Next animation. Very little of it. Tweens and that's it. Lip syncing was just moving the mouth up and down. More animation to keep us interested. That just takes practice.
I hope Im not being too harsh, because I do think you've got the skill to make a sweet movie, and not too shabby of a story to work with. Just keep practicing and you'll get something out there.
Good luck.