By most accounts, “Star Wars: The Force Awakens” is the biggest blockbuster in the series. The relaunch of the space opera franchise opened like gangbusters for The Walt Disney Co. (NYSE: DIS) in December 2015 with nearly $248 million domestically and went on to gross $937 million in North America. But the original “Star Wars,” released 40 years ago by 20th Century Fox (NASDAQ: FOXA, FOX), was an even bigger hit.