1)Metroid- This series was my first video game in 2004, my first Metriod game was Metriod Zero Mission on the gameboy advance. I have played Super Metriod,Corruption,Prime,and some more.
2)The Legend of Zelda- 2005, a year after I played Metroid, my first game was A Link to The Past, took me a month to beat it. I've started to become a huge fan of this series, I have played LoZ,OoT(it's been a lonnnnng time since I played this game),MM(another game that's been a lonnnnnng time since I played it), FS,FSA,TP,ST,PH
This one is actually a tie between two series 3) Kingdom Hearts and Super Smash Bros- I can't explain what I like about these series....
Honorable Mentions- Pokemon,Final Fantasy,Naruto,Sonic The Hedgehog,Megaman,Castlevania,and about 15 thousand more games...
1. The Legend of Zelda (favorite game: The Legend of Zelda: A Link to the Past)
2. Mario (including every game with Mario in it that comes from Nintendo... favorite game: Paper Mario)
3. Tie between Pokémon, Metroid and Mega Man (favorite games: Pokémon Yellow, Super Metroid and Mega Man 3, respectively)
3 changes a lot, depending on the day, the first two will always remain as my favorites.