I have a somewhat unique Star Wars theater experience: in short, I didn't have one at all (even though I was 7 in '77).
See, our family stopped going to movie theaters around 1975 or so after a bad experience while seeing Bambi at the drive-in: the theater showed a trailer for The Texas Chainsaw Massacre during intermission. My parents were so horrified that they decided they would never go back to a theater again... and they didn't, at least not until after I had grown up and left the house.
So I never did see Star Wars in the theater originally.
However, that didn't stop me from becoming the biggest Star Wars fan in my school. I read the novel, the comic books, the Scholastic storybook, listened to the Story Of Star Wars record, and collected the cards and action figures. And I was hooked.
There was actually a point where my 4th grade class took a field trip to go see Star Wars at the local small town theater (a field trip I suspect my teacher may have arranged for my benefit to give me a chance to see the movie). Parental permission had to be obtained for us to attend, though. Sadly, after some debate my parents decided to stick to their guns on their decision... and I ended up being the only student in the class who had to stay at school by myself and do busy work while the rest of the class went to see Star Wars. Oh, the tragic irony!
In fact, the first Star Wars film I saw was actually The Star Wars Holiday Special when it aired in 1978. Which might explain a few things about my acute interest in that particular, er... masterpiece of cinematic accomplishment.
The first time I actually saw Star Wars itself was around 1984, when I was in high school and it had just come out on videotape. Pan-and-scan on a television screen. Not quite the ideal experience, but I was stoked anyway. And it was just as good as it had been in my head all that time.
Kudos for my parents for sticking to their word, but in this case I think their staunchness was misguided. Yet, perhaps it's because of all this that I became the kind of dedicated Star Wars fan I am now.
--SKot