I definitely have hazy memories of seeing ANH during its theatrical run in the 70s, probably during one of its many re-releases. I would have been only 3 or 4 at the time, but it still made a big impression on me.
My parents even took me and my brother to Toys R Us afterward to buy some Kenner action figures.
I have clearer memories of seeing TESB in 1980.
I voraciously consumed all the EU I could get my hands on throughout the 90s.
My enthusiasm for the IP never recovered from the prequels, unfortunately. I still follow it, but not with the same level of autistic obsession that I used to.