Being born in 1989, I didn't really get a chance to see the originals in theater. In fact, I didn't even remember seeing Star Wars until I was maybe four or five? Maybe six? Not a clue.
I'm not sure why I saw it. I just remember a trip to the video store and coming home with Star Wars. I have a notoriously shit long-term memory, but I still very clearly remember seeing Darth Vader for the first time.
I'm not sure the film stuck with me right then or not. I do remember seeing at least The Empire Strikes Back with my cousin during either a re-release of the originals, or the theatrical run of the SE when I was seven or eight. Very clear memories of being in a theater watching the scene where the wampa attacks Luke. No idea which theater it was. Pretty sure it was in Tucson, though.