Audio books?
I'm enjoying 'Luka and the Fire of Life' by Salman Rushdie. Depends on the 4 year old, but it's 5 hours long!

http://itunes.apple.com/us/podcast/all-ears!-audiobooks-for-family/id263497549
has 'Phantom Tollbooth' which my son loved at 4. Not sure if it's the whole book or not.
DS also liked listening to the Oz books
http://www.booksshouldbefree.com/book/ozma-of-oz-by-l-frank-baum
Frank L Baum, not Gregory Maguire's version.
Don't feel like you have to start at the beginning - I think Baum was learning his craft on the first one, and I could never get through it.

If you have time to preview, you may enjoy reading aloud the series - http://www.amazon.com/Fairy-Illustrated-AUDIO-Download-ebook/dp/B0076GX3KK
Problem is that some of the stories are just too scary at age 4, 8 or 48!

Good luck!

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