Nobody should underestimate Tolkien's contribution to the canon of English literature in general, or his influence on the genre of fantasy in particular. His body of work is epic in scope and impressive in detail. I know an awful of lot people for whom Tolkien is the begining and the end - no other writer comes close. His work has been translated into numerous languages and three fine feature films have brought his work to life on the screen.
However, for every Tolkien fanatic I know, I can also point to a barely touched copy of the Fellowship gathering dust in an attic. Many readers fall by the wayside without really denting the tome. The Lord of the Rings(LOTR) Trilogy is hard work - there's just too much noise getting in the way of the story and the characters. You really need to perservere with the LOTR. Sometimes it seems that Tolkien has deliberately thrown obstacles in the reader's path to test their resolve or worthiness - archaic language, agonising digressions, turgid poetry and songs that make you want to leap out the window.
Tolkien will still be read in a hundred years I'm sure, and rightly so. Just don't go buy the books because you liked the films. If your typical novel experience is an easy holiday read - a Dan Brown or a Michael Crichton, or your attention span isn't better than the average Joe's, then steer well away. Otherwise, it just might change you life. ( Kind of! )