I have not read all pages of this thread, so forgive me if someone already said this.
The problem with Peter Jackson's version of the destruction of the ring is that his screenwriters did not fully understand the story and what happened. In the book, as Sam and Frodo are struggling up Mt Doom, they are attacked by Gollum. Frodo finally throws Gollum down and, clutching the ring in his fist, he says (may not be an exact quote) "If you touch me again, you shall be cast yourself into the fire." That was a command that Frodo made upon the ring, even though he may not have realized it when he said it. He has commanded that Gollum fall into the fire if he touches Frodo again, and it is that command that causes Gollum to fall into the fire in the book.
