To me, neither.
To many, a hero. He inspired an unknown amount of people to do their art - paint something, play music, whatever.
Hell, even now/recently there was a movie based around their music, pretty good too.
I enjoyed the Beatles. Well, most of it, their later psychedelic stuff aint really for me. But while I dont consider him a hero, I dont know what 'bad' he did to warrant the 'heel' tag either.
Funny, though, as I was just reading into his death recently. I think the anniversary just happened. I think.
Im making a 'this day in history' PPT for my class, including some famous people born that day and events, and I remember seeing something about this in the early September area.
His killer is in the last picture of (alive) Lennon. Shot him multiple times and then waited on the police to arrive to arrest him. Weird.