I have a different perspective than many of you in that I'm old enough to remember standing in line for the OT for its original releases ( high school for ANH, college for ESB.) Of course I loved the OT, but in the intervening years before the PT, I was not particularly active in SW fandom. Sure, I read many of the EU books and collected a few things, like my Revenge of the Jedi sweatshirt, but that was about the extent of it. I eagerly awaited the release of the PT, and after AOTC, I wrote an outline for a story telling the events of the OT, but from Vader's perspective. The notes got filed away, and I forgot about them until the release of ROTS when, like everyone else, I was set on fire by that movie.
I think what struck me hardest about Anakin's fall was how young he was when it happened. Having grown up with the OT, I always envisioned Vader's move to the Dark Side as a conscious, rational decision made by a mature(30+) person, not as a emotional, inadvertent choice made by a young person. It totally changed my idea of who Vader was, and I became completely fascinated by the character. Instead of coldly calculating, he was fiery and passionate; instead of being a machine, he was all too human. I began to write Vader stories that integrated the two trilogies, and that's still my favorite type of SW story to read.
As for my Vader question, I just spent twenty minutes fruitlessly combing through Dark Lord for a quote that I know I read in an official piece of fiction. Anyways, the quote basically said that Vader's Force vision abilities were burnt out on Mustafar. Certainly it's been stated in many places that his injuries and artificial limbs decreased his ability to use the Force, and that some skills, such as Force lightning, became completely impossible for him. I'm interested to hear how you all view this issue, and how his access to the Force was changed by his injuries. C'mon, don't you think he should have been able to fold his arm and shoot Force lightning out of his left elbow? :)