It is a really good movie. The second best movie in the original trilogy after Empire strikes back. When I first watched all the Star Wars movies, this was my favorite. I love the ewoks and how they were able to defeat AT-AST's and clone troopers. The space battle was not as good as that of A new hope, but it's still good. The battle between Luke and Vader is one of the best duels. The last 40 seconds of the duel is one of the best scenes in all of Star Wars. Luke was the best hero in that movie - from his green lightsaber, saving his friends, ready to risk everything to turn his father back to the light and eventually being successful in it. Vader's redemption was perfect and this was the true ending of the saga. I really liked that there was a lot of action.
I have 2 small complaints - one is that there was too much time spent on Jabba's palace and the other is that the emperor died WAY too easy.