My details are sketchy... the movie begins live action and a little girl becomes a cartoon and shrinks to bug size in her backyard. There was a praying mantis, I believe there was a caterpillar that became a butterfly in the end of the movie...
That's about all that I remember... I had to have been 6 or 7 years old. Please Help!!

Sounds like Dot and Keeto (http://www.imdb.com/title/tt0090960/)