Easter egg: Go to disk 1 "Play Movie". Hit right to highlight the owl to see Harry's Hogwarts letter.
Easter egg: In the 2nd disc, go into the Humans Only door. When all the doors in the vault have stopped and have all been activated by Boo's laugh, hit left to highlight DVD Credits, and you'll view them when you hit enter.
Easter egg: In the DVD Menu, go to "Extras." This menu should have the Gingerbread Man on it. Move around and hit right to select the Gumdrop buttons. You can now see various bits of trivia from the production of "Shrek." This easter egg is found only in the Region 1 DVD.