One other point about the 1977 Star Wars movie, before Lucas 'updated' it... (Yes, dammit, Han shot first!).
Star Wars hit the theaters in limited release on May 25th, 1977. Wide release didn't occur until July 15th, 1977, partially because Fox wasn't quite ready for how well received the movie was.
Star Wars cost $11 Million dollars to make (in 1977 dollars that was A LOT). Since that time, it has grossed $775,398,007. Not bad for a movie made in 1977...
Here are the numbers for how much money it took in in 1977:
http://boxofficemojo.com/movies/?page=weekend&id=starwars4.htmWhen it first came out, 20th Century Fox was taking a gamble of sorts. NO movie like this had been done (this being the era of police/car chase movies and such). 2001, Silent Running, etc. were all fairly grounded in science, whereas Science Fantasy was a new thing to many audience members (Flash Gordon/Buck Rogers aside).
Add the budget that was spent on Star Wars (which was a lot of money at that time), and the fact that it could have very easily went the other way (flop/mediocre), and you can see why it being successful was such a big deal.
Note that Logan's Run was released almost a year earlier (June 23rd, 1976). It cost around $9 Million to make, and only grossed around $25 Million, with another $9.5 Million being made in Rentals. This gives you some perspective as to how Star Wars MIGHT have fared...
As a young moviegoer, I had NEVER seen anything like this in the theaters. Star Trek - The Motion Picture was still 2 years away. Battlestar Galactica didn't come out until July 7th 1978. Star Wars broke a LOT of new ground, in the special effects department as well as for the Genre in general.
Sure, there was a lot of 'B' movie quality sci fi that had been around since the Flash Gordon days, but this was simply on a whole new level. Plus, it had some great acting talent that simply gelled well together, even if we didn't know who the heck played Darth Vader (James Earl Jones did the voice, of course) until much later...
Heck, putting your main villian in a full suit, behind a rigid face mask was itself a risk of sorts...
Star Wars was a big deal when it hit the screens. In comparison, Episode I was simply a continuation of an already successful franchise. Sure, the special effects were cool, but that ground had been broken a long time ago.
For you younger types who didn't get to see Star Wars in 70 MM in 1977, well you missed out. Of course, home computers were not quite a reality yet in 1977 either, you kids are so spoiled!