Hard choice for new school i think PS2 because I've played that more than probably any other console, it has a shitload of games. it started many great franchises like Jak and daxter, god of war, Devil may cry, among others. it continued franchises like metal gear solid. great controller. Backwards compatible.my only complaint for it has been my 1st one is busted due to a problem i don't completely understand but it's apparently common in the original models.
for older id say SNES for mostly the same reasons except backwards compatibility, also i didnt have to replace it