The conventional Hollywood wisdom has long held that religious and family-friendly movies are not high earners. But this wisdom is beginning to wane in the face of recent theater trends. The five top-grossing movies so far this year are rated either PG or PG-13, and all of them have surpassed the $100 million mark. Two of last year’s top 5, Shrek 2 and The Incredibles, were PG-rated animated films. This kind of success is causing executives to rethink their standard fare. Family-friendly movies, especially animated ones, have brought people to the movies who haven’t gone in years. And they will...