The beautiful thing about home theatre is that you can watch this important film in the way it is best enjoyed.
First, you should watch The Empire Strikes Back if you haven't enjoyed it recently, just to set everything up.
Now you have a choice. You may choose to watch the short Star Wars film Escape from Jabba's Palace. This short feature is shown at the beginning of Return of the Jedi and runs about 1/2 hour. It comes in two versions, with the "special edition" version featuring an enhanced musical number. It also features a cameo by the enigmatic Boba Fett.
You may also skip Escape from Jabba's Palace without any significant loss to the storyline.
Now, the main film. Again, it's about 1/2 hour long. It's the story of the redemption of Anakin Skywalker. We follow along as Luke Skywalker travels to the "forest moon of Endor," ditches his loser friends and goes on to rendevzous with his father. Inexplicably, the film is intercut with something called "Ewok sequences." Since I have never watched these since the film debuted in the theatre, I can't say much about them except that you can fast forward past them without loss.
Thus we come to the moment that three (or indeed six) films have been leading up to -- the man who was Anakin Skywalker must make a choice on which the fate of the galaxy hinges.
Despite the disappointment many fans express with this film, I enjoy the climactic scenes with Vader, Luke and Palpatine. I also love the vocal chorus that's Palpatine's leitmotif ... I wish we heard more of it. In fact, the arrangement of the John Williams score, including the pianissimo strains of the Imperial March in Vader's last scene, are wonderful.
Of course, I would change the ending (minor spoilers):
EXT. EWOK VILLAGE SQUARE - NIGHT
Rebels and Ewoks join together in dancing and celebration. The original group of adventurers watches from the sidelines. Only Luke seems distracted, alone in their midst, his thoughts elsewhere.
He looks off to the side and sees three shimmering, smiling figures at the edge of the shadows: Ben Kenobi, Yoda and Anakin Skywalker.¹
The ghostly Anakin looks over at Obi-Wan, and his face contorts in rage. Anakin's image flickers and winks out.
EXT. VADER'S FUNERAL PYRE
Vader's form stirs on the flaming pyre. His right arm raises and the fist clenches.
The Dark Side is stronger!
EXT. SPACE - ENDOR
The forest moon continues to rotate serenely for a moment as the Rebel Fleet orbits nearby. Suddenly the moon is racked in a paroxysm of convulsions. It explodes violently, wiping out the Rebel fleet in a series of minor secondary explosions.
END CREDITS OVER STAR FIELD.
Children in the front row of the theatre may cry now...
1. These first few lines are taken from the official screenplay.