Dick Van Dyke -- 'Mary Poppins' Author HATED MY GUTS!!!

The author who created "Mary Poppins" had a spoon full of HATRED for everyone affiliated with her movie ... this according to "Poppins" star Dick Van Dyke.

DVD -- who played Bert in the 1964 classic -- was out in Malibu yesterday ... and told us he was super-excited about Tom Hanks playing Walt Disney in an upcoming movie about the making of "Mary Poppins."

But Dick explained ... there was some MAJOR DRAMA behind the scenes, telling us author P.L. Travers -- who created the Mary Poppins children's books -- battled Disney for 20 years before begrudgingly allowing him to make the film.

"She didn't want to do it," Van Dyke says ... "She just hated the idea ... she hated Julie [Andrews] and she hated me."

In fact, Travers hated the movie so much, she put it in her will that NO AMERICANS shall ever be granted permission to work on a Poppins project ever again.

We also asked Dick if there was any truth to the urban legend that Walt's head was cryogenically frozen -- but it's clear DVD ain't buyin' the rumors.