No.
It's complicated. I firmly believe that you shouldn't have to believe in a fictional figure (even if he is based off of a historical one) to find sufficient joy in the holidays.
Then again, it's fun. It's nice to pretend to be a kid again and track Santa on the NORAD website, even if I know he isn't real.
I hate getting gifts from my family from "Santa". I always want to say "I know he's not real, I can recognize your handwriting, guys", but I can't because there are younger kids in the room.
I'm not Christian, so I don't celebrate Christmas like many in the world do (I do go to Christmas and I wish people a Happy Christmas, but I don't do mass or any of the religious aspects of it). I celebrate the solstice which is a happy time for me anyway, so I'm always happy around the holidays even without believing in Santa.