Count your blessings that this movie was not made.
I can only acknowledge that John Boorman was quite young in his writing career at this point. Certainly the screenplay suffers by trying to squeeze the entire novel into one film, in a 176 page treatment. If I had not read the novel previously, I would have been bewildered by the inexplicable haste with which Bilbo appears and is hastened off the screen by Gandalf who, having badgered him into giving up the Ring, forces it upon Frodo and sends him packing within moments, too. The immediate appearances of Black Riders and then of Strider appearing out of nowhere just in time for Frodo to be stabbed and then saved the next day at the "crystal palace" of Rivendell (all in the space of what seemed to be four or five days of movie time) would have boggled the imagination and the credulity of the unprepared viewer. I can only imagine what the reaction at United Artists must have been to this hasty treatment.
Of course, I should not get too hasty myself: I've not finished the text. I was distracted by a much more agreeable conversation with a young professor of psychology who was doing some research of his own on Memory and Tolkien's form of creativity. Still, when I got to the Kabuki Theatre-style re-enactment of the history of the Rings in Rivendell, and the description of the actor portraying Sauron in this elvish theatre as a "combination of Mick Jagger and Punch," I quite felt that the script suffered a fatal case of... 1970.