Grew up watching mostly on TV. Still old enough to remember the world standing still for the Trillia in Manila and the Rumble in the Jungle. But who made me a life time fan was Hagler. I thought man that's one scary dude. Later on I became a hard core Duran fan, then Gatti fan etc, so with the exception of Ali, I generate like warrior type fighters who are willing to put everything on the line. I'm a year or two older than Tyson but I remember being memorized by him in my early 20's, part of me thought he was invincible and part of me thought he was going to go off the rails, so his loss to Douglas, while surprising, wasn't a total shock. Been a Lewis fan since day one but that's probably because I'm Canadian and he won us a Silver and Gold metal.
I would say Tyson but I was just a kid, did not watch boxing consistently because of him, same with Chavez. It was Tito that coincided with me being an adult and giving me something to be PRoud of. The hard punching (either way) the drama, the momentum swings. Tito fights had it all.