Lord of the Rings is without question the best movie adaptation of any book ever. Do you prefer the Theatrical or Extended movies? My thought is that the extended editions are worth it, but I also understand not wanting to watch a four hour movie.
Tolkien's works truly defined fantasy, creating the modern perceptions of Elves, Dwarves, and Orcs. He even created a new race of Hobbits or Halflings which has become increasingly common in fantasy. Tolkien's writing can sometimes be unnecessarily wordy, such as saying "sons of my father's daughter" instead of nephew's for example, but I love this sort of thing.
It's also my personal head cannon that D&D is set in the fourth or fifth age of Middle Earth, long after the events of Lord of the Rings.
In my opinion Tolkien wrote the Holy Trinity of fantasy, The Silmarillion, The Hobbit, and The Lord of the Rings. I can not stress how amazing the high fantasy of the Silmarillion is. If the Lord of the Rings is the New Testament, the Silmarillion is the Old Testament, steeped in lore, and just as convoluted.