I freely admit that I only hold positive thoughts for Jedi because it's lumped in with the OT and was the first Star Wars film I saw in the theaters. And I saw it at age 6, which was the perfect age. I dug the ewoks, I had the action figures, I'd spent the past few years running around with a whiffle bat pretending to be Luke Skywalker, and when the blizzards that hit Philly in the early 80s hit, and I was less than 4 feet tall, the sidewalks became the trenches of Hoth.
But when I watch Jedi these days...yeah, I see the flaws. I see them in the first two as well, but the first two are a lot less childish, as Cayman describes, and have fewer gags, as Got Wookie points out.
For me, Jedi survives for three reasons and three reasons only:
1.) The effects shots are still pretty cool.
2.) It completes the OT story (albeit perhaps not the way it was originally intended).
3.) Nostalgia.
Outside of that, I'd say it's tied with ROTS. ROTS, in some ways, is more appealing to me, although I find ROTJ to end more naturally than ROTS does.
Anyway, I think both ROTJ and ROTS aren't quite crap films, but they're definitely flawed, and definitely STRONGLY influenced by their precursors. ROTJ ends up being more enjoyable because it has the first two leading into it, and ROTS suffers because it has the first two prequels laying its foundation. In terms of the raw potential available in each storyline, though, I think ROTS had the potential to be leagues better than ROTJ, but that would've required basically erasing the first two prequels and redoing them totally differently. Likewise, ROTJ could've been total crap, but wasn't because the first two OT films are so closely tied to it.
P.S. It's not "Anakin's story."
