There's really only two main things I would emphasize.

First off, there was the major alteration of the movies through the use of technology that didn't exist when they were originally shot and released (something that, to the best of my knowledge, was unprecedented in 1997).

Going off of that, you could go into how Lucas stopped labeling the SE as the SE, first with the 2000 vhs set and then the 2004 dvd (which was technically a further altered version).

Secondly, I would bring up the release of the GOUT and all of the problems it entailed, not the least of which was George going back on his "This is it" stance regarding the SE.