Imagine you are David Cronenberg, a filmmaker but also a parent. You tell your kids that your job is making movies; naturally, they want to see one. So which do you show them? "Scanners," with its exploding heads? "Rabid," where porn-star Marilyn Chambers drinks human blood? Or maybe "The Fly," where Jeff Goldblum transmogrifies into a gnarly-looking insectoid creature? Maybe not.