Of the versions I've seen (1937/1968/1982 animation) this is the only one that really gets the story right! For starters, instead of the typical blonde we now tend to typecast Heidi in, we get the little brown-haired girl that Spyri depicted in her book. She wears simple clothes, not the traditional Swedish outfit, because they recognize that she was poor, and those clothes are only worn on special occasions anyways. The movie doesn't try to stray away from the original story with overt dramatic subplots, it simply depicts the story as it was originally told, and as the book is a very simple story, that's very hard to pull off in a movie. I was so glad that they didn't write out more minor characters like Tinette, Grandmamma or the Doctor. They just enrich the story so much and were played beautifully.
Only real critiques: They changed Schwanli and Bearli's names, and changed the name of the Alm Uncle to Uncle Alp. Also the Irish Accent of Emma Bolger could get a little distracting, and Fraulien Rottenmeier and Aunte Dete were a little crueler towards Heidi than I remember... but considering all that was included I was very satisfied. Makes me want to read the book all over again!
Definitely not a story for those who crave a lot of action and drama. But if you absolutely loved the book as a child, this is a great companion piece.