Though this comment is only tangentially related to the topic, I found Dracula to be the worst boss (besides Zangief, perhaps, whose brokeness makes him a mere inconvenience).
The joy of most of the game is being presented with challenges that, at first glance, seem maddeningly difficult; and then, after some persistent trial and error, finding apparent impossibilities to be reliably conquerable. With Dracula, however, victory seemed to depend more on waiting for Dracula to use the right attacks to allow you to destroy him. While I'm sure that devoted players that gather here have little problem dealing with any attack thrown at them, most players will find that some attacks are much more likely to kill them than others. If you play Dracula enough times, he will eventually use enough of his useless attacks in a row to allow you to dispatch him in relative safety.
Because there's so much luck involved, it feels like much less of an accomplishment to beat Dracula. (Which is ironic, since he's much harder than Tyson, Clown Copter, Birdo, or Zangief.)