Probably #10, David Tennant. He was the first actor I ever saw in the role so that might have something to do with it, but he of all the Doctors I've seen he seemed the most alive. Second would be Matt Smith, his take on the Doctor has certainly been interesting, although I didn't really like last season for dragging the Doctor through the mud, but that's hardly Smith's fault. I have only had limited exposure to the classic Doctors, thanks to Netflix Canada's extremely limited selection of Doctor Who episodes, but I can see why people like Tom Baker though.