Gregor and the underland
Cirque du freak
Alex rider series
The demonata: lord loss
harry potter series
Maximum ride series
found (about time travel) by margret peterson
percy jackson and the olympians
The kane chronicles
The epic of gilgamesh
Don't read Metro 2034 and 2035. The first one is fantastic, but the other two are just bad.
If you want to read more about the metro-universe, try books from Andrei Djakow. (I don't know if they are available in English^^)
any book with a rating over 4 is absolutely great. type some books you liked and you'll get recommendations. This website helped me find so many great books
For medieval fantasy, I'd recommend: "the name of the wind" - P. Rothfuss
I hate reading, absolutely loathe it but that's because I can't concentrate on it. (concentration deficiency)
But somehow I was absolutely captured by the following book series:
Chronicles of Ancient Darkness/Wolf Brother series by Michelle Paver and The Song of Ice and Fire Series by George R.R. Martin.
Seeing as no one mentioned it, the lord of the rings books are pretty good.
Also even though this isn't the type of book you were asking for Matrix III, Volume 1: The Psycho-Social, Chemical, Biological and Electromagnetic Manipulation of Human Consciousness by Valdamar Valerian is a must read if you're into books.