One way to define literature would be to say "required reading in our high schools and colleges." However, I've seen some of the required reading lists that are currently in vogue and you'll never get me to agree that the Twilight series is great literature.
My interest will wax and wane depending on the books. I would be interested, for example, in books by Sinclair Lewis, John Steinbeck, or Ernest Hemingway, but not interested in anything by Bram Stoker, Louisa May Alcott, Charles Dickens, Herman Melville, to name a few. It is not that I don't recognize their work as great literature -- hard to say Dickens or Dumas pere is not of that class -- rather, it is that I am not interested in the 19th century writing style.
One way to solve the problem may be to limit the work to particular time periods and available from the MobileRead library. Just consider anything available in the MR library to be literature.