Goey Louie, pick his nose but watch out if you pick the wrong thing his brains will pop out AHHH 
Pic Pirate Pop Up Pirate. Pull the knives out of the Barrell but pull out the wrong one and he will suddenly jump in the air. 
Crocodile dentist, pull on the wrong tooth and he will bite you ! 
3 good fun games with a element of suprise which will make everyone laugh
And importantly easy for young children so they have a chance of winning.