What's funny about Bobby Orr is, most people won't dispute Gretzky is the greatest of all-time, but I bet there isn't a player in the history of the game who is more fans favorite all-time player than Orr.
Like in my parents generation, they were kids before the Canucks came into the league. My Dad was 13 in 1970, so he was already a big Bruins fan and Bobby Orr before the Canucks were the big thing in town. This is true for most my family of that generation and anyone else I know from that time. At least half of them would say Orr is their favorite all-time player, despite being lifelong Canucks fans.
I suppose this could be true for Gordie Howe, but in my experience that isn't the case. Though I guess that is a whole generation older than Orr, and there just isn't as many people around that remember those days, sadly.
Mario Lemieux. I watched his NHL career start to finish. As I was such a fan my family tried to go to Pittsburgh some time each march for a couple days, IF Lemieux was healthy, and if the Pens had 2 home games over 3 or 4 days. We went in 88, 89, 92, 93 and 96. A couple of years he was healthy in March, but a couple months earlier, when my parents needed to buy tickets, his health was too iffy. For 1993 they bought tickets a couple weeks before the cancer announcement, and we were sure he would never make it back in time. Actually, we were worried he would never play again, but he made his amazing return a couple weeks before the two games we had tickets for - those two games were back to back 4-goal games. It was complete madness.
Lemieux always played better at home, and always seemed to play his best in March and April. Watching Lemieux on TV was amazing, but watching him from the stands....was something else (and even more amazing the 3 games that I had front row seats). He put on a show every single time - from signing autographs and chatting with fans during the pre-game warm up to simply doing things I have never seen anyone else do. He scored at least one goal in each of those 10 games I attended. I was a kid, and it seemed like he was doing that just for me. I remember in one of those games...against Calgary I believe, it was an empty-netter in the dying seconds of the game, but still, that goal meant so much to me because he always scored when I was there, and I knew that he would always come through for me. He was simply amazing.