The Cat in The Hat is probably the most famous beginner book.  With such famous characters as The Cat in The Hat and Thing One and Thing Two This book could only be Dr. Seuss.  It has been translated into Braille, French, Chinese, and Swedish.

One Fish Two Fish Red Fish Blue Fish uses the repetitive element that Dr. Seuss used often.  It also is a great resource for children to learn to count.  This book has become so popular that it even appears on many clothing items. 

Green Eggs and Ham is another one of Dr. Seuss's more famous books.  It also host one of Seuss's famous characters, Sam-I-Am.  This book even inspired an actual dish of Green Eggs and Ham.

I'm Not going To Get Up Today was written in 1987.  This was the second to last book Dr. Seuss wrote before his death.  This, said Geisle, was how he always was as a child.  He never wanted to get up and begged his mother to let him sleep in.

I Can Read With My Eyes Shut was written in 1978.  It was written as part of the beginner books collect for young children learning to read. 

In true Dr. Seuss style, There's a Wocket in My Pocket rhymes completely.  Written in 1979 There's a Wocket In MY Pocket was the shortest book Dr. Seuss ever wrote.  This story hosts the same characters as Seuss's first book, And to Think It Happened On Mulberry Street.