I would love to say that it's the Dreamcast but I started with the Master System even before the NES, those damn moments playing Double Dragon with my cousins were awesome also the fact that we had infinite lives before the last level was the best idea ever, don't have to say that when I noticed that Mordecai and Rigby had this console it bring me back tons of good memories ;D
(http://junkee.com/wp-content/uploads/2013/05/RegularGamingMain.jpg)