I realize the Silmarillion won't be for everyone; it won't be for most people. It is not a novel or a short-story collection -- it's a book of myths and legends of Middle-earth written in a sort of King James biblical prose. The tales range from the creation of the world (and the rebellion of Melkor/Morgoth, of whom Sauron was merely his chief lieutenant) through the rise of the peoples of Middle-earth (Elves, Dwarves and Men) and great Wars of the Jewels (the Silmarils proper) to the departure of the last elven ship into the Uttermost West sometime after the end of the War of the Ring. To (mis)quote from Tolkien, here you will find much of beauty and much of sadness.
And you'll also find, if you're so inclined, the deeper tales that underlay most of the songs and poems in The Hobbit and The Lord of the Rings.