Yeah, I am aware that this topic has more likely than not been covered many times over... but I'm still new here.. so you'll have to give me a chance to lend my voice to the proceedings...anyway.. onward...

Episode 1 introduced the concept of the Chosen One, and the Prophecy of the One who will bring Balance to the Force.

Yoda: "Master Qui-Gon... more to say have you?"
Qui-Gon Jinn: "With your permission, my Master. I have encountered a vergence in the Force."
Yoda: "A vergence, you say?"
Mace Windu: "Located around a person?"
Qui-Gon Jinn: A boy... his cells have the highest concentration of midi-chlorians I have seen in a life form. It is possible he was conceived by the midi-chlorians."
Mace Windu: You're referring to the prophesy of the One who will bring balance to the Force...you believe it's this boy?"

And in Episode 2, I believe..

"Remember, Obi-Wan. If the prophecy is true, your apprentice is the only one who can bring the Force back into balance."
- Mace Windu

For me, personally, this added a very cool dynamic to the story. This idea that Anakin's role in the galaxy was fortold, and almost expected...It was a very interesting concept. Say what you will about midichlorians and wether or not their introduction and inclusion in the saga was needed or worthwhile...the concept of a "vergence" and "The Chosen One" really hit the mark for me. It gave Anakin's fall that much more drama.. the golden boy of the Jedi, their savior, this pre-ordained hero proving them all wrong... Force Choking huge holes in their theoriesand beliefs... Or did he? That is the real question here. And frankly, in my many hours of mulling this over I am able to come up with more questions than answers...But let me try to put it all together....

The prophecy says that the Chosen One will bring balance to the Force. Now, when I first saw Episode 1, I spent a great deal of time internally debating what that all meant. I knew Anakin was the Chosen One, and knowing what Anakin was destined to eventually do... I tried my hand at piecing it all together. First off, us fine fans, being well versed in the lore of Star Wars, and having seen Episodes4-6, know what happens already. We know that Anakin aids in bringing the Dark Side into power and brings about the downfall of the Jedi Order. Now how does that tie into this prophecy? and the real problem is.. what exactly do we mean by "balance" After TPM I had come to the following conclusion... Balance would mean all things equal...in Anakin's time, there were many Jedi knights (10,000 according to the TPM novel)... and only 2 Sith. So wouldn't that mean that Anakin fulfilled his role in the porphecy by reducing the number of Jedi to be about equal with the Sith? is this a Jedi prophecy or a Force prophecy.. for there are others in-tune with the Force who are not Jedi... do they know of the prophecy? The Force is not alone dictated by Jedi and Sith... So how does balance lend itself to these other Force Sensitive cultures? (The questions continue at infinitum it seems...and I'm afraid it'll have to wait for another blog)

Then we add yet another complexity to the puzzle... we add a bit of "unofficial" lore to this story.

And in the time of greatest despair, there shall come a savior, and he shall be known as: THE SON OF THE SUNS."
- Journal of the Whills, 3:127

This certainly lends eveidnce to Anakin being the Chosen One, the savior who would come in the time of greatest despair. I find this a bit conflicting though... The Clone Wars were obviously a tough time for the galaxy... but their time of darkest despair? Wouldn't the Empire's control of the galaxy be far worse? So, wouldn't that also lend credence to Luke being the Chosen One? We'll come back to that point in a second...

Once again.. what do we mean by Balance? Upon Anakin's immolation on Mustafar, Obi-Wan in his despair reveals a bit more...

"It was said you would destroy the Sith, not join them! Bring balance to the Force, not leave it in darkness!"

Episode 3 adds that little bit about the Sith to the prophecy.. which makes it a bit simpler... it lends belief to the porphecy being a Jedi/Sith creation.. and not a creation of the Force as a whole. Which in terms of the films would make sense for the Jedi and Sith are the only aspect of the Force we have any contact with. So, if we follow what is said in Revenge of the Sith, balance is returned to the Force through the destruction of the Sith.
Which , if we go back to Luke... would rule him out as the Chosen One. I feel Luke's role in the prophecy was more of a catalyst for events, and perhaps a greater ultimate roleaftrwords...The definitive answer; however, comes from George Lucas himself during the Episode 3 Audio Commentary. He maintains that Anakin Skywalker is truly the Chosen One, and not Luke, arguing that it was Anakin who ultimately destroyed the Sith, by destroying both Sidious and himself.

Look at it in a different way.(with the knowledge we have of the outcome of Anakin's life) We can see, throughout the Prequels, just how imperfect the Jedi Order is at this time. Perhaps due to the Jedi's decreased abiltiy to control the Force? (as Mace Windu alludes to in Attack of the Clones) They may not understand it all. And even Yoda mentions that they may not truly understand the prophecy fully... Does anyone? Yes... Obi-Wan does; as did his master. He may not really know it... his knowledge may be more innate regarding it, but he has the right of it... Anakin's fall to the Dark Side certainly weaken's his belief, and maybe creates a "deception" to fool his thoughts... that is one of the Dark Side's strengths is it not? Qui-Gon Jinn also had his focus in the right place. He had his mind in the here and now. Mindful of the future, but not at the expense of the present. Yoda could not forsee Anakin's future.. and those whose minds wandered away to the future... did litle but worry, and would have led the Chosen One away from his destiny if not for Qui-Gonn. He knew the vergence he had found was the Chosen One... and Obi-Wan, taking his master's wisdom came to believe it as well.
"He won't let me down... He never has." And he didn't...

As I write this, (as I'm sure you've noticed) the ideas seem to sray a bit... which is one reason I wanted to write this, to "reason" it out in words... In Episdoe 2 Yoda makes mention of how arrogant the Jedi are becoming, that their focus is not what it once was...perhaps this balance not only included the destruction of the Sith... but also the Jedi. That would indeed be a true balance. I do not believe that notion is too far off. In return of the Jedi, Yoda as he lay on his death bed, tells Luke that he is the last of the Jedi (regardless of how many may or may not have survived Order 66). So is it possible thatLuke is upsetting th balance then? The balance his father dies for...perhaps not. The Jedi are meant to be in tune with the Force. There is the code...
There is no emotion, there is peace.
There is no ignorance, there is knowledge.
There is no passion, there is serenity.
There is no chaos, there is harmony.
There is no death, there is the Force.
-The Jedi Code
Perhaps, the Jedi of that time had strayed too far from it.. even wise master Obi-Wan was not at complete peace... his love for Anakin an infuence on his actions... perhaps then Luke is meant to restore the Jedi to what they should be. Afterall, he had very rudimentary training compared to the Jedi that came before him, he did not have a grand temple to study in, or even a government to serve... He was left to begin anew with not but the Force and a little guidance to aid him. Thus the old Order falls, the Sith fall, and the galaxy and the Force are returned to the state that was intended for them. Balance is achieved at last...thanks to Chosen One. He came at their darkst hour, the son of suns, the savior, and he fulfilled his ultimate destiny. Now... this blog is already running long so I won't delve into the other related questions... and we shall call this fini... for now...

(note- I have not read the NJO order series. so if anyone has knowledge from that source that supprts this, or denies it.. I'd love to hear it.)