Here are a few books which will not just occupy your time, but fill it. Some titles are the first in a series; in each case the entire series is recommended.

Achebe, Chinua
Things Fall Apart
Alexander, Lloyd
The Book of Three
Bradbury, Ray
Fahrenheit 451
Dostoyevsky, Fyodor
Crime and Punishment
Eco, Umberto
The Name of the Rose
Garcia Marquez, Gabriel
Chronicle of a Death Foretold
Heller, Joseph
Catch-22
Herriot, James
All Creatures Great and Small
Keillor, Garrison
Happy to Be Here
Lewis, C.S.
The Great Divorce
Pratchett, Terry
Lords and Ladies
Rowling, J.K.
Harry Potter and the Sorcerer's Stone
de Saint-Exupery, Antoine
The Little Prince
Shakespeare, William
Hamlet
Steinbeck, John
The Grapes of Wrath
Twain, Mark
The Adventures of Huckleberry Finn