These movies established what the entire franchise has become in a very similar way to how Walt Disney helped establish his company by re-releasing proven successful features.
The backstory of the reference I make goes back to the historic example of Snow White and the Seven Dwarfs. On more than one occasion, Walt Disney was able to re-publish Snow White and people would return to see it again and again. During most of these time frames, home theater systems or recording devices did not exist. It was worth the money to make a night out of it.
George Lucas pulled this page right out of Disney's book and rolled the dice by re-releasing Star Wars in theaters in the 1990's. It broke records and children too young to see it before got to have the experience. I was born in 1985, when Return of the Jedi was in the movies. I was one of the children that got to enjoy the experience of it coming back.
Today, such marketing tactics are not showing as much success. We live in a world of infinite re-boots and almost anything can be downloaded if you find the right place to go. Most people are capable of equipping their living to cater better to their needs than any movie auditorium can.
The only Oscar won in any of these movies was by Obi-Wan in A New Hope. Star Wars did not start at the very beginning and thrived from doing so. Lessons about film making and script writing have been learned since these movies made it big.
Harrison Ford is really the only one who was not too negatively affected by Star Wars in terms of their acting careers. It has been said by many that the association with their Star Wars characters, took away from other performances.
I remember the first time I watched Star Wars on video cassette. They were amazing then and they are still amazing now. It is not often you see classics like this out value movies made with larger budgets and far more superior technology.
I am very excited to see Episode VII in December. I hope that J.J. Abrams does not disappoint and I have no reason to suspect that he will so far. Try to stay away from the rumor mill. I have heard about somethings and there might be an article out there or two, you may want to stay away from.
I am also going to have to find a way back to Disneyland, with the recent announcement made about the construction of a Star Wars Land part of the park. Hopefully, Disney will know how to cater to fans both young and older as they develop the concept beyond what any of us could come to expect.