Either an Atari or a Commodore 2000. I'm no longer sure which one it was but I do remember that I played Pacman on it.
Several years after that my friends from school started playing Mario etc. on the NES. But I didn't. In fact I didn't own any consoles after that until I picked up a 2nd hand N64 purely for the purpose of playing Mario Kart and GoldenEye for old times' sake.
My first actual game system(i hope this counts) was a Nintendo DS Lite for christmas of 2008. It was really exciting for me and the first game i played was Bionicle Heroes. It was suprisingly a GREAT game and i beat it 3 times. Then i got my Xbox 360 and i basically ignored it forever.