Yeah, LOTR's plot is so ridiculous, it only created the entire fantasy genre as we know it today. Besides having the most intricate world ever created, it is a hell of a lot more than "walking to a volcano". You can oversimplify any plot like that if you so desire.
-Harry Potter is nothing more than a child wizard going to school.
-Donnie Darko is nothing more than a kid dealing with wormholes.
-Kill Bill is nothing but a bride seeking her revenge.
-The Titanic is nothing but a love story.
-The Dark Knight is nothing more than Batman fighting the Riddler.
-Star Wars is nothing more than a drawn out fight between the Jedi and the Sith.
-Casablanca is nothing but a love story.
-The Matrix is nothing more than a man finding out he lives in a virtual reality controlled by machines.
-12 Angry Men is nothing more than a jury reaching a verdict.
-Eternal Sunshine of the Spotless Mind is nothing more than people erasing their memories.
-Die Hard is just a guy fighting some terrorists.
Above I have listed some mediocre movies, as well as some of the best movies ever made and most intricate plots ever designed. Note that regardless of the actual complexity, all of their plots can still be described in one sentence if I try. All you're doing is vastly oversimplifying what is commonly held as the greatest trilogy ever made, along with each individual movie easily in the running for one of the best movies ever made.
Here, have fun with this "simple" map of just the actions of each individual character in the movie, let alone how they all come together and the vast amount of underlying mythology and story. Also, feel free to check out the other maps below, including the beloved Star Wars to see the difference in complexity.
http://imgs.xkcd.com/comics/movie_narra ... _large.png
Of course, if you really wanted to understand the world created in Lord of the Rings instead of just that brief glimpse, you'd have to read the 365 page book "The Silmarillion" to understand all the underlying ideas and mythologies that are very frequently alluded to, referenced, and actively involved in the story.
For the record I can put up with a lot of bullshit on this forum, but bashing LOTR goes too far.