As for the easter eggs on Disc One, Here are the guidelines for you to access them via DVD Player. I've discovered them myself.
How to access the BNL Easter Egg
On the main menu, press down until you reach the "Bonus Feature", from there, click left and then up. It will point you to the BNL Logo.
How to access the circle with letter W Easter Egg
On the main menu, press down until you reach "Set Up" from there, press right and then up. It will point you to a circle with the letter W.
As for the Easter Egg on Disc 2, I haven't seen it yet.
To add, I really love the twist after the end credits.
WALL-E is brought to you by BNL!