Actors is Actors
Today, Gentle Reader, you get two days for the price of one. That's because I don't separate actors into male or female. It's a long story, having to do with my evolving dislike of gender and sexual segregation by language, to which I won't subject you. Just know that "favorite actor" and "favorite actress" are non-starters for me. Therefore, as I said, two for one - and a very image-heavy two for one at that; you've been warned.
Days 25 and 26 - Favorite Who Actors
Billie Piper - I didn't know her as a pop tart sensation, I didn't know her at all when I first watched Billie Piper in "Rose." After I saw her smile of pure joy, running into the TARDIS for the first time, after I watched her face in "End of the World," processing the reality of being billions of miles and years away from home, after I watched her deal with her father's unexpected life and deliberately chosen death in "Father's Day," I knew she was an actress of unusually intelligent and intuitive power, sparkling with wit and wonderful comic timing, full of a natural grace. I've seen her since in other things, and they have reinforced my opinion of her.
Catherine Tate - I can't believe that I disliked this woman's characterization of Donna the first time I saw her in "The Runaway Bride," because she is magnificent. Her range absolutely floored me, and she's made me want to watch her in other roles. Tate's abilities just prove that that if you can handle the intricacies of comedy, you can act, and do it well.
Matt Smith - that an actor this young can make me believe he is a 900-plus-year-old entity, both kind and completely "other," is a testament to his abilities. My only request of him is that he slow down his delivery a little bit; it makes Tennant's delivery sound like a New Hampshire farmer's. That tiny quibble aside, Smith is the Doctor for me, as Eccleston was. He just shows a completely different side to the Doctor, one he makes me eager to travel with.
Alex Kingston - Because she's River Fucking Song, that's why. Seriously, Alex Kingston, besides being breathtakingly beautiful, has the acting chops to create a complicated, emotionally and morally ambiguous woman of brilliance and bravery. I may have problems with Steven Moffat, but River Song, as interpreted by Kingston, is definitely not one of them.
Tom Baker - The Fourth Doctor is not My Doctor. But I'm surprised at how often I can be impressed with Baker's performance, a compelling mix of joy, intelligence, anger, wit and power. The fact that he became The Definite Article for generations of viewers wasn't solely due to the length of time he spent in the role, not by a long shot.
Lalla Ward - I include her and I'm not quite certain why, beyond the fact that, whenever people mention "Doctor Who actors," she immediately springs to mind. I take that as indirect proof of her ability to make the character of Romana II come to life; Ward's Romana is cheeky, distantly cheerful, both more mature and less cynical than her original incarnation - and indisputably as alien as her partner in crime, the Fourth Doctor.
William Hartnell - It's sad to know that Hartnell had problems remembering his lines at the last, because every time I see episodes with his First Doctor, I am so bloody impressed with his sly but loving interpretation of a crotchety and selfish old runaway Gallifreyan, whose sole initial claim to grace is the love he bears his granddaughter. He has a deceptive frailty, which hides brilliance and a growing conscience as he becomes fond of his human
Other honorable mentions: John Barrowman (Captain! Jack! Now, with added and sometimes unexpected depth and power); Jon Pertwee (the other My Doctor, a tall, elegant lisping man of action who is the magnificent Third Doctor); Lis Sladen (Sarah Jane - as graceful, loving, and irritably independent in maturity as she was spunky, brave and idealistically independent in youth.)