Who are the characters that were, when you started reading comics, different from what their iconic status quo and/or original version is?
I'm not sure my formulation is clear, so I'll start with my own examples.
Iron Man. When I started reading comics, Iron Man was James Rhodes. For me, Tony Stark was just some homeless drunk guy that Iron man happened to know.
Captain Marvel. My first CM was Monica Rambeau and it was only a long time later that I learnt about Mar Vell.
Banshee. He was not the guy with sonic powers, but some sort of James Bond like badass character with a gun and micro bombs. (it was during the time he couldn't use his powers)
Klaw. Funny and nutty. This one sticked with me. Even after all those years, Klaw is still for me that phony guy from Secret Wars.