The original Phantom Edit cut out a few unnecessary scenes, speeding up the pace of the film.
Jar Jar is sort of necessary, since he leads the Jedi to the Gungan city to get the Bongo sub to escape to the city of Theed.
The later Edits are much better, as they give the Gungans/Neimodians an alien language with subtitles, so no annoying voices (though technically all they did was give reverse speech). The subtitles are also different so that the plot changes (the opening crawl also changes, so it's not over taxes, but slave trading). Much more interesting, though you have to go with the other edits of the other movies too since the plot changes. The original edit was based on the VHS tapes, the later ones have the DVD material to work with (including deleted scenes) and so end up being much better, IMHO.
A fan edit of Star Wars I saw that I really liked gave Jabba new lines (you could also just skip the scene he's in entirely), so that he came down harder on Han, and thus seemed more threatening. Plus they edited the Death Star plan schematic so it actually matched the Death Star model we see onscreen. That one was cool!