Iconic/Classic: Frankenstein's Monster/Boris Karloff, Dracula/ Bela Lugosi, Phantom of the Opera/ Lon Chaney Sr.
Modern: Leatherface/Gunnar Hanson, Freddy Krueger/ Robert Englund
Favorite: Frankenstein's Monster/ Boris Karloff and Leatherface/Gunnar Hanson. I would say Lon Chaney Sr, Bela Lugosi and Robert Englund would be other favorites of mine also.
Up and running: Chucky, Norman Bates and Hannibal Lector/ Present Favorite: Sam from Trick or Treat and Krampus.