I have been working with my student in Stafford on The Hobbit by Tolkien (the same author as The Lord of the Rings and a big success in the movie theaters this winter). We were talking about the movie and the book last session and we agreed that the movie does not follow the book so closely but it is fun and interesting anyway. The message it conveyed at the end, that Bilbo was in the adventure to help the dwarves to get their home back, makes sense in the Tolkien universe and agrees with the hobbit's way of life and ideas.
Bilbo is between the devil and the deep blue sea all the time in the book, because he is his own antagonist, and keeps always thinking of going back to his comfortable home in his village. Last session we discussed what is for me the climax of this book because it is the moment when Bilbo decides, once and for all, to become a real hero. He is in the tunnel that leads to Smaug's cave (Smaug is the bad guy in this story, the dragon that stole the dwarves gold and destroyed their city and is now sleeping on his loot). Bilbo, as everyone knows since the beginning, is a hobbit hired as a burglar by the dwarves to retrieve their gold and riches. How exactly he is going to do that, he himself does not know but since he is a burglar he assumes he has to go in quietly and steal something to show the dwarves he can do it. Well, when he stops just before getting to Smaug's lair and thinks of what might happen, this is the moment in which he decides between being just a common hobbit and a heroic one. Tolkien explicitly says (chapter 12) that in this moment, in the tunnel, before entering the dragon's lair, there was a battle raging inside Bilbo's head that was more intense that everything that would come after it (and a lot happens after that, as the reader will see in chapters 13 onwards). I'm curious to see how the director will convey that in the upcoming movies (in the one that will be in the theaters until the end of 2013, the Desolation of Smaug).
So, in The Hobbit, parts of the book actually hint at the significance of each character's action. Tolkien helps the reader at this point by making it clear that Bilbo's internal struggle with himself (Took X Baggins) is the true conflict going on in this book. In fact there are plenty of antagonists but his Baggins side is the real big obstacle to his progress in this journey.