Which of the Fellowship would have gone ring mad?

[The Saucepan Man]

For that matter, is thread revolving around the book, or the movie?

Any discussion of this nature which concerns the films should be in the Movies Forum. My understanding, however, is that this discussion concerns the book, and I have certainly made my comments on that basis.

I agree with Son of Númenor that, given a long enough exposure, every member of the Fellowship would have succumbed to its power. This may not be expressly stated in the book, but I think that it is implicit in the nature of the Ring, which was created to assist Sauron in his purpose of enslaving all within Middle-earth to his will. The only possible exception would be Gandalf, but given the consequences if he did succumb to it, I wouldn't fancy taking that risk.

I probably sound like a scratchy record as I keep saying this on the forum, but Tolkien made it clear in his Letters that no one could voluntarily have destroyed the Ring. This is consistent with the story, since it would belittle Frodo's efforts, in my view, if someone else could have succeeded where he "failed". And Frodo's inability to destroy the Ring was not because he suddenly decided that it was rather pretty and should not be harmed after all. It was because the will of the Ring itself prevented him doing so. It follows that, if Frodo finally succumbed to the will of the Ring, then (Bombadil excepted) there is not one who would not also have succumbed to it eventually.

Now if it was a Fellowhips of Frodo & Eight other Men , well, than that'd be quite a bit different.

While I think that its fair to say that Men's will to resist the Ring is weaker than that of other Races (they were, after all, the only ones ensnared by the Rings of Power), it does not follow that the other Races were not vulnerable to it. The Dwarven Kings might not have been enslaved by the Seven Rings, but they were certainly affected by them. And the Elves must have recognised their vulnerability, since they removed the Three and kept them concealed when they perceived Sauron's plan. There is, I think, a tendency sometimes to think of Elves as all but flawless and therefore dismiss Legolas as a contender for submission to the Ring. But lets not forget that there were some pretty flawed Elves in the First Age. Eöl and Maeglin, for example. And then there were all those Elves whose pride and possessiveness led them to run around chasing the Silmarils for thousands of years. And I'm not just talking about Feanor and his sons. Thingol too lusted after it, and Legolas was a descendant of his people.

For all these reasons, and because they were much closer to Frodo and therefore less likely to be tempted into attacking him, I think that the Hobbits would have been more able to hold out than either Legolas or Gimili. It's a tough call between those two, but I put Legolas first because Dwarves are said to be able to resist at least one aspect of the Ring's power, namely its "enwraithing" effect.

And finally, let's not be too down on Isildur. If you accept that no one could willingly have destroyed the Ring, then Isildur can hardly be blamed for refusing to do so. Also, he did come to think better of his decision to keep it as a weregild for his father. When he died, he was on his way to Rivendell to seek the counsel of the wise on what should be done with it. So I do not think that he necessarily had any less self control than Aragorn. But, being Men, I still think that they were both more susceptible to it than members of the other Races.

Edit: To respond to a point made by Olorin:

If Gandalf or Aragorn did it, they'd do it, as I've said, for the defense against Sauron, and so I think first they'd try to convinnce Frodo

By the time that anyone else in the Fellowship succumbed to it, I don't think that Frodo would have been able voluntarily to give it up. So it would either have to be stolen (unlikely to succeed) or taken by force.