I was five and a half when Episode 4 came out in 1977.
Episode 5--eight and a half.
Episode 6--eleven and a half.
I watched them on video a few times, after VCRs became common, and eventually understood why Han kept calling Luke a kid, and also why some people didn't like any of these movies that I enjoyed so much.
Some time in college, in the early 1990s, a friend informed me that the three existing movies were actually the middle three of nine. That George Lucas had started with the middle three because they required the least special effects, and that he would make the rest when the technology was available for him to realize his vision. We probably debated what order they should be watched in, by future generations who hadn't seen the first movies before the last ones were made.
I didn't think much more about it until probably fall of 1998, when my husband and I were waiting for some other movie to start and a huge green field appeared on the screen. Lumpy things rose over the top of the hill. They moved slowly over the top and down. They opened up and disgorged row upon endless row of what I now know are battle droids. I could hardly remain seated when I realized what was going on.
Some time between the releases of Episode 2 (2002) and Episode 3 (2005), my husband and I had a son. Now the question of what order the next generation should watch the movies in became more important. Still, I had time to think. [parental naivete]He wouldn't be ready for such scariness and violence until he was at least seven.[/parental naivete].
Well, now it has begun. Someone in my son's day care class has been humming John Williams's soul-stirring Imperial March, and it caught his fancy. Before I knew it, my baby (now four and a half), was playing a computer game that put him in the pilot's seat of an X-wing fighter. He already knew that Darth Vader used to be Anakin Skywalker. (Why did I think that any sentient, English-speaking person might be able to reach the age of seven without finding that out?) He was eager to watch the movies, and I would rather he see them before he gets the idea that it's all just about shooting at bad guys from a space ship. Yeah, I know I'm mostly kidding myself that it's about more than shooting bad guys from a space ship. But still. I figured that maybe he was ready, and I was sure tired of waiting. As luck would have it, we have dvds of Episodes 1 and 2, so tonight, a half hour before his bedtime, we let him watch the first 40 minutes of Episode 1.