I think my favorite would be to use the theatrical crawl for episode 4 to just show it as the original first film; STAR WARS. And the subsequent movies are also apart of the STAR WARS saga but with added subtitles like STAR WARS: THE EMPIRE STRIKES BACK and STAR WARS: RETURN OF THE JEDI.
Basically just how it was before the prequels came out, except you remove any reference to an episode number.