A false Star Wars movie memory from me:

I always recalled in RoTJ since I was a kid that after the Ewok glider gets shot down that you see a shot of the Ewoks watching from the trees and then you see the AT-ST stomp on and smashing (walking over) the fallen glider.

Once I got the DVD I realized we never actually see this happen, though its pretty clearly implied by the editing. Glider falls... we see the ewok reaction shot and a close up of the fallen glider and then we see the walking legs. No actual smashing going on (and no, as a kid I didn't cover my eyes!). Obviously my imagination filled it in, though!

Less of a false memory and just forgetting, my younger brother and I listened to the ROTJ storybook & record so much (before we had a recording of the actual movie), we forgot that many of the lines in it are different from the film.