For those that have tried, but cannot penetrate these types of books, start with any Nobel Literature winner that looks interesting. They are the gateway to serious literature, and by reading the recognized "best written intellectual novel of the year" you'll be gradually exposed to the writing structures used in harder to penetrate literature.
Don't be fooled into thinking that a Nobel Literature winner is difficult to read, none of them are and that is why they have the award. They are also white knuckle rides through tragic human lives where the main character wins against incredible odds, and these novels demonstrate the critical thinking and secondary considerations necessary to prevail when others are crushed. Great literature teaches one first hand how to use critical thought, a dire need today.