Thor: The Dark World," the latest blockbuster based on Marvel's iconic comic book character, took a hefty $86.1 million in its opening weekend, figures from Exhibitor Relations showed. Starring Australian heartthrob Chris Hemsworth as the hammer-wielding son of Odin, the movie is a follow-up to the franchise's 2011 money-spinning first installment, "Thor." Although the opening was far less lucrative than other recent superhero movies in the "Iro...