In general, I would keep people and places from the film and post-ROTJ eras that occur in several books, video games etc, but not all the stories. Keep stories that expand on the story of side characters we see in the movies, such as the bounty hunters, etc..

Do away with weird science (that belongs in Star Trek :-þ ), Force mumbo-jumbo, surviving Jedi, new superweapons, aliens from outside the galaxy, etc.

Some post-ROTJ EU characters have many fans, and I think that it would be a bad move of Lucasfilm to just delete them. I am thinking primarily of the Rogue Squadron, Mara Jade, the Organa-Solo kids. Perhaps Kyle Katarrn, but I am not sure.

I would not mind if the pre-prequel eras EU was wiped completely.