Technically Sam is the hero of The Lord of the Rings. He's the only character who carries the Ring and feels no temptation by it, while even Frodo and Bilbo give in to the Ring eventually and try to keep it for themselves, because Sam's desires are ordinary and simple - he just wants Rosie, a happy home and a family, and has no interest in the power that the Ring tempts him with. The only reason he even carries it for a while in the first place is to take the burden off his friend Frodo. I also wonder if this is one of the reasons why it didn't have much of an effect on Bilbo for much of the time it remained in his possession, and only really took control of him when he was very old, weaker-willed and living the life of the closest thing Hobbits have to celebrity. Thus a big moral of the story is that you're better off keeping to achieve these fundamental, but boring in the eyes of many, necessities - adventure, fun, riches, rulership and seeing the world are all very well, but they won't give you the same satisfaction that a peaceful homely life with a loving family and friends does.