Imagine it's June 1982, and you're faced with a decision at the multiplex between two new movies, "Poltergeist" (released on June 4) and "E.T. the Extra-Terrestrial" (released a week later, on June 11). Which film about a suburban family whose lives are overturned by a supernatural alien presence do you want to see? At the time of their release, the horror/satirical approach of "Poltergeist" and the mythical/sentimental approach of "E.T." seemed to be at opposite ends of the spectrum. Yet, three decades later, the two movies have more in common than near-simultaneous release dates, suburban settings, and otherworldly fantasy/horror/sci-fi elements: they also sprang from the mind of Steven Spielberg and explored many of his signature themes. Spielberg himself noted the similarity in a June 1982 interview: "I think people lead lives where their deepest wish is that something would interrupt the mundane everyday routine," he told Michael Verona. "And...