Which would be your favorite?
Just curious to see what people like, since each series appeals to a different type of gamer. Final Fantasy for people who like cinematic stories and gameplay that's practically reinvented with each new game. Dragon Quest for people who are nostalgic and crave the simplicity of old-school RPGs. And Megami Tensei for those who like something that's in-between, with gameplay that evolves more than DQ but less than FF, and occult-flavored plotlines. (at least, that's how I see them)
I picked Megami Tensei, which is funny, since I'd never heard of the series five years ago, but Persona 3 got me stated and Nocturne hooked me for life. It feels like the most intelligent and thought-provoking of the three series, with plotlines that really delve into some of the deeper aspects of the human psyche. The Persona games even introduced me to the theories of Karl Jung, which I've since grown fascinated by and plan on studying more in-depth at some point.