The  Count of Monte Cristo is a great book, but I wouldn't recommend it for learning english. The abriged (short) version is 450-500 pages. The original version is around 1000 pages.

You'll want to stay away from Shakespeare and Charles Dickens until you're fluent with your English ability. Eventually, you should read them.

Instead try these books. They'll be easier, and they are books that a lot of people in the U.S. read when they are kids, while they were growing up: 

The Chronicles of Narnia by C.S. Lewis - There are 7 books.

The Hardy Boys by Franklin Dixon - There are many books

Tales of a Fourth Grade Nothing by Judy Blume

Charlotte's Web by E. B. White

Superfudge by Judy Blume

Hitchhikers Guide to the Galaxy by Douglas Adams

The Hercule Poirot Mysteries by Agatha Christie - There are many of them

The Adventures of Tom Sawyer by Mark Twain

The Adventures of Huckleberry Finn by Mark Twain

I second the "Little Prince" recommendation. Anything you've read in your native language is a good choice.

Also, just follow your interests: I read an English translation of "The Book of Tea", a book about Japanese philosophy and aesthetics, when I still lacked a lot of vocabulary, but I kept at it with passion because I found the subject compelling.