I remember a boy and a dog.. possibly St. Bernard.. they drive around in a little red car.. it goes in and out of reality and animation.. there was a red and white striped barber pole.. and there were clouds.. I know this movie is somewhere.. if you can help me at all.. it would be greatly appreciated.

Possibly The Phantom Tollbooth (http://imdb.com/title/tt0064806/) (1970)