Don't Let the Pigeon Drive the Bus by Mo Willems. Pigeon has been a favorite since he was very little. He used to flail his little arms at the "LET ME DRIVE THE BUS!" page.
Knufflebunny, Knufflebunny, Too, Knufflebunny Free by Mo Willems.
How Do Dinosaurs Say I Love You by Jane Yolen
Any of the Skippyjon Jones books by Judith Byron Schachner.
Story of Ferdinand by Munro Leaf.
The Quiet Book by Deborah Underwood
Splat the Cat by Rob Scotton