Pretty much any Nintendo franchise. Mario, Zelda, Donkey Kong, Pokemon. Nintendo was what I started with, and up until the PS2/GC Age it was all I had. I've wanted a Wii for the longest time not really because of any game that's on it, but because it would be the perfect current-gen console to finally go back and play everything on GC I never got the chance to.
Non-Nintendos I can think of would be Megaman, Suikoden, Okami, Soul Reaver/Legacy of Kain (This series would probably be the ONLY movie-based-on-a-game that I would willingly pay to see, ON OPENING NIGHT no less).
And, as loathe as I am to admit it, WoW...Not Blizzard, but WoW. The only Blizzard product I had ever played before WoW was Diablo 2, and quite honestly...it was a lot of fun the first time through, but once I opened up the Pandora's Box that is Multiplayer, it became such a massive grindfest that I lost interest, and the discs are still piling up dust in my closet to this day.
But WoW, on the other hand, is like being in love with an abusive BF/GF. You know they're the worst possible thing for you, but you just can't stay away. I've "quit" the game three times already over almost as many years, yet I still find myself constantly keeping up on patch updates, hoping for the day when things will finally stop being such shit.