All time favorite fiction writer: Flannery O'Connor. Anything she's written I've read several times over and I teach her fiction in my literature course.
Some other standouts for me:
Non Fiction: C.S. Lewis' _Mere Christianity_
Fiction/Literature:
_Light in August_ by William Faulkner
_Dead Souls_ by Nikolai Gogol
_Pride and Prejudice_ by Jane Austin
_Pilgrim's Progress_ by John Bunyan
Children's Fiction
The Harry Potter Series by J.K. Rowling
_The Lion, the Witch, and the Wardrobe_by C. S. Lewis
_Tom's Midnight Garden_ by Phillipa Pearce
_The Man_ by Raymond Briggs (Picture Book)
If you have children you absolutely must read the Pearce and the Briggs book, although the latter is hard to find in the States. Both are simply lovely and timeless.