SUPER ANNOYING BROS

Braxten got a Nintendo DS for Christmas and is addicted to Super Mario.  I remember a few tricks from the countless hours I played this game when younger.  Granted, it has evolved a little bit - like I don't remember snow and ice.  Or bats!  So the questions is: "how much game play is too much?"  And when and where is is appropriate to play?  In bed? At restaurants? In the car?  First thing?  Last thing?  What are the best boundaries?  And why is this particular game so addicting?  I have to wonder if its the same goofy music and bells and almost wins and that make slot machines to enticing...