I cant say that there was just one game to be honest. Super Mario Bros (NES) got my hooked as a kid. Stonekeep (PC) was my first experience with RPG and was a lot of fun. Chrono Trigger (SNES) my favorite console RPG. Ocarina of Time (N64) really got me into Action/Adventure games. Tribes (original - PC game) was some of the most fun I had gaming and gave me the interest in FPS. Starcraft (PC) really got me interested in RTS games. Myth: TFL & Myth2: SB (PC) really are just awesome games and while they are not technically RTS increased my love for that genre. World of Warcraft (PC) really got me to appreciate and enjoy modern RPG games.