If I were 10 years old, would I be badgering my parents to take me to see the new Batman film, The Dark Knight? You bet I would. It's the latest and biggest release in the superhero genre, which children instantly understand as a direct appeal to their special interests. It's also touched with the alluring suggestion of forbidden fruit: the maniacal, deranged face of The Joker, grippingly played by the late Heath Ledger, leers from posters all over town. If I were the parent who relented and took a 10-year-old child to see The Dark Knight, would I be...