Andrew Stanton, the writer/director of Finding Nemo (my favorite Pixar movie) did a seminar which (for a portion) talked about pitching your story.  It's available on Youtube if you want to watch the entire thing, but the gist of it is listed below, summarized by a Youtube patron named boxiness (thanks for the summary).  I've included the summary here, in case you don't have time to watch the video.

Also, feel free to look up Emma Coates (Pixar) formula for story formats Pixar style.

- A story should start off with a well-told "promise", like a hook or sales pitch

- A story should give the audience the "2+2", not the "4"

- Characters should have "spines" & itches they're always trying to scratch

- Change is fundamental; life is never static

- "Drama is anticipation mingled with uncertainty"

- Know your rules and know when to break them

- Strong unifying theme

 

            -  Sense of wonder