A fan or not, it's hard to get around the fact that Middle Earth is at the front for blockbuster movies. There have been five so far, each installment getting an extended version, and people flock to watch the movies and buy the videos. And why wouldn't they? With wizards capable of unique and powerful magics, bizarre and neat looking monsters, elves capable of superhuman feats, and even humans wading into these fantastic tales, the stories seem to have something for everyone.
And then there are five hobbits - Bilbo, Frodo, Samwise, Peregrin, and Meriadoc. They can't do magic, they are no more clever than we are, they are nothing more than short humans. And yet it is their successes that allow evil to be defeated. They aren't put in unrealistic situations, either. Each character is drawn as a real person with deep flaws. Each of them is accidentally thrust in a position of temporary importance during the course of the story. And all five come through when they need to.
Perhaps Tolkien was a master at making the average person look important. Maybe the personal aspect of the hobbits' characters allowed him to generate a much greater feeling of closeness to them than we might otherwise have felt. But the fact is that hobbits make Middle Earth work. They are the only characters to be trusted with the ring. They hide it, they travel with it, they destroy it. They make the trip to Moria possible, they bring the Ents into the war against Sauron. They bring the human/elf/human trio into Rohan where they save the king and protect its people from invasion. One saves the Gondor seneschal's son. Others are better fighters, better strategists, better speakers, but without the hobbits nothing happens.
I don't think that Tolkien had intended it, but it's easy to see the hobbits as the real heroes of the stories. Throughout the books, all the other characters do what they do whether that be fighting, talking, healing, or working magic. But hobbits are farmers, craftsmen, and carpenters. Simply leaving their Shire was outside their normal life experience. And that is only the beginning. The five grow so much in their time away. They become thieves, diplomats, soldiers, and a dozen other things in their adventure. Together, they manage to end the eons-old threat of Sauron; the struggles of the rest of Middle Earth are really no more than distractions for that goal.
Perhaps that is one more layer of Tolkien's Middle Earth. That, for him, the hero isn't necessarily the man who has volunteered and trained to serve his country who is the real hero. Instead it's the person thrust into a role he isn't bred or trained for who manages anyway. I always like to keep in mind that he and his three close friends were drafted into World War I, a role none of them were ready for, and only Tolkien survived. Maybe, just maybe, the Middle Earth stories originated as his way of saluting their sacrifice, of recognizing what they could have been, and of bringing attention to the significance of their lives. In that way, I think he immortalized them all.