"Eat" Cried Little Pig by Jonathan London - A Little piggie's first word is "Eat" and as he yells it he makes a huge mess while doing so. A fun read aloud because you can do some really funny voices for the pig and his family. Be careful to get the comic timing of this one down before you read it with your kids.
Z-Z-Zoink! by Bernard Most - Boy does the pig in this story snore! He can't seem to find acceptance anywhere on the farm.
Piggies in the Pumpkin Patch by Mary Peterson- I am not super crazy about this book but I think it would work fine with 2 year olds. The text does nicely wrap throughout the story becoming part of the illustrations. This could also be used as part of an Autumn themed story time.
Pigs to the Rescue by John Himmelman- A great refrain that kids will have a blast shouting out loud.