Read first, or watch first?
Either order works, and for a young or easily-scared kid the film first is a genuinely good door: it is gentle, Dove-approved, and its goblins scare almost no one — and it cannot spoil the book, because the best of the book (the tower, the songs, the teller's voice) is exactly what it leaves out. Families who read first lose nothing either; the film's plot tracks the book closely enough that it plays as a reunion. The DVD of the 1991 film is inexpensive and easy to find; there is no other adaptation worth the name.