Here’s a list of things added/changed in the 1997 SE
Additional dewbacks and search teams are visible as the Stormtroopers search for the missing droids. An Imperial transport can be seen taking off in the background.
There is a new shot of the evening Tatooine sky that tilts down, transitioning to the scene in which R2-D2 is captured by Jawas.
The Jawa sandcrawler is revised.
The sunset progression is enhanced, with the sky darkened and stars added at the end of the sequence. The scene in which R2-D2 is captured is tinted red to resemble a sunset.
The interface on Luke’s viewfinder is altered.
A new digital matte painting of the sandcrawler and extended sky is added when the Jawas are setting up shop in front of the Lars’s farm. Artificial zooming-in is also present. More vaporators are added; they disappear in subsequent shots.
There is a new establishing shot of Ben Kenobi’s hut.
Many new shots and elements are added to the Mos Eisley spaceport. There are new CG shots of the Mos Eisley skyline, and added people, Jawas, Stormtroopers, Rontos, and other creatures.
The blur under the landspeeder is replaced with a more accurately shaped shadow.
Ben Kenobi’s line of “this place could be a little rough” just before they enter the cantina is a different take.
New aliens are seen in the cantina.
During Han and Greedo’s conversation in the cantina, the word “yes” in Han’s line, " Yes, I’ll bet you have" is not audible (but still visible).
In the cantina, Greedo fires first as Han dodges the shot and then returns fire on Greedo. This is one of the more famous and controversial changes to the film, giving rise to the saying, “Han shot first”.
A new scene has been added in which Jabba the Hutt confronts Han in the Millennium Falcon’s launch bay. This scene was originally a deleted scene from the 1977 film, with actor Declan Mulholland playing Jabba. A computer-generated Jabba replaces Mulholland, accompanied with new dialogue recorded in Huttese.
There is a new shot of the Millennium Falcon taking off from Mos Eisley.
In the shot where the planet Alderaan is destroyed by the Death Star, an explosion ring is added.
The Death Star docking bay is revised to be more consistent with the one seen in Return of the Jedi, most notably in the overhead shot when the Millennium Falcon lands.
C-3PO’s line describing the tractor beam’s power systems has been restored after being omitted in previous stereo sound versions.
Some shots of Imperial officers being shot by blasters have been censored. The first few frames of these shots have been replaced by extra frames from the previous shot, usually a shot of someone firing a blaster at the officer.
When Han Solo chases a squad of Stormtroopers on the Death Star, he no longer runs into a dead end; he ends up at a hangar bay with many Stormtroopers and officers.
The line, “close the blast doors!” has been restored into the scene where Han and Chewbacca, pursued by Stormtroopers, jump through the blast doors as they close.
Two shots of the Millennium Falcon approaching Yavin have been completely re-shot.
The Falcon can now be seen landing on the 4th moon of Yavin.
A new digital matte painting is used in the establishing shot of the Rebel base temple.
Additional fighters have been added to the matte painting of the Rebel hangar.
A scene between Luke and Biggs Darklighter just before the attack on the Death Star has been inserted. This was originally a deleted scene from the 1977 film.
There are new CG shots of fighters taking off. In the original version, the fighters appeared as white spots of light flying off into the distance.
The fighters’ approach to the Death Star is now presented as a single shot, instead of two shots in the original version.
During the attack on the Death Star, many shots of the dogfighting and attack run have been replaced by brand-new CG shots.
After Red Leader’s unsuccessful trench run, the line “He’s on your tail!” was added.
The shot of the Rebel fighters flying away from the Death Star has been revised.
The Praxis effect was also added to the destruction of the Death Star.
When Luke, Han, and Chewbacca approach the throne, matte paintings of assembly members on the sides of the throne room have been digitally replaced with real humans.
James Earl Jones is now credited as the voice of Darth Vader.
“Luke’s Theme” is partially repeated in the ending credits music to accommodate the added Special Edition release credits.