I remember enjoying the Pipi Longstocking books in elementary school, and my 4-year-old loves this movie. As an adult, however, I find it painful to watch. It isn't that the movie is bad, at least not in the same sense that schlocky sci fi and horror movies are bad. The children do acceptable acting jobs, although the adult actors are lackluster. The sets, costumes, and special effects are adequate. The music is bouncy. There are lots of fun Pipi stunts and much childhood wish fulfillment. All good, clean fun. Somehow, though, the film is less than the sum of its parts.
I think it must be the plotting and pacing. The super-competent Pipi so outmatches her opponents -- a villainous real estate agent and an uncompassionate human services worker -- that you never feel any suspense or concern for her safety. In fact, Pipi comes across as such a smart-mouthed brat that I began to sympathize with her playmates' whiny father. The story itself meanders from incident to unrelated incident until the movie positively drags.
So, this is a movie that it is safe to let your kids watch unsupervised. That's a good thing, because you won't want to sit through it yourself, at least not more than once.