I tried to rank my Doctors from most to least favorite but as I worked and re-worked the list, it became apparent that it's just impossible to make a definitive decision. The series has been incredibly lucky in that they have manged to cast 11 actors who all brought a high degree of charisma and magnetism to the role - there have been bad episodes, even bad seasons, but never a bad Doctor. But let's take for granted that Tom Baker is "my" Doctor, and then just list them in order...plus, in a timey-wimey bit of editing, I've updated the list to retroactively include developments that happened after this was posted on November 23!
WILLIAM HARTNELL (First Doctor, 1963-66)
A grandfatherly figure out of Dickens working the controls of a malfunctioning time-ship - steampunk starts here, kids. The first Doctor could be snappy and stand-offish when he wasn't giggling at his own cleverness, an absentminded professor with a shady past fleeing his homeworld in a ship he only barely understood. Hartnell's Doctor started out frankly scary and ended up entirely loveable, as his friends and companions taught him what it meant to be a hero.
Especially notable in the original era of Doctor Who is the revolutionary title music and graphics, which anticipate electronica and psychedelia just as the 1960s are getting into full swing. And let's not forget the debut, in the show's second story line, of the legendary Daleks.
KEY EPISODE - See how it all began in "An Unearthly Child," or check out the very touching BBC-America made-for-tv movie "An Adventure in Space and Time" about how the series got its start, starring David Bradley from Harry Potter and Game of Thrones as William Hartnell.
PATRICK TROUGHTON (Second Doctor, 1966-69)
A manic, scruffy little hobo with a basset-hound face and a twinkle of mischief in his eye, this Doctor clowned and bumbled his enemies into the jaws of destruction. His diminutive height and jackrabbit skittishness made the towering monsters he faced seem even more intimidating, but he always got the better of them in the end. Troughton faced the task of playing the first "New Doctor" and selling the regeneration concept to a skeptical public - without his brilliant portrayal we wouldn't be talking about the show to this day. He was a great character actor and physical comedian, fully capable of playing both the Doctor and an evil lookalike with utter credibility, and also had my very favorite psychedelic title sequence.
KEY EPISODE - The Doctor and his friends find themselves caught up with an archaeological expedition unwisely trying to open "The Tomb of the Cybermen."
JON PERTWEE (Third Doctor, 1970-74)
Just in time for the glam rock era, Doctor Who went to full colour with the flamboyant Third Doctor. This dashing man of action sported kung-fu moves, a wardrobe of velvet and ruffles, a variety of James Bond gadgets and vehicles, and an air of charm and sophistication that made him one of Britain's most beloved stars.
KEY EPISODE - The Doctor fights living mannequins with the help of the paramilitary organization UNIT in "Spearhead from Space."
TOM BAKER (Fourth Doctor, 1974-81)
The one and only Tom Baker is still considered by most as the definitive portrayal of the Time Lord. With his hypnotic stare, toothy grin and absurdly long multi-colored scarf, his Doctor was a bohemian adventurer with a quick wit and devil-may-care attitude, mad as a hatter and impossible to take your eyes off of. He was a Doctor for all seasons - sometimes goofing around with a Python-esque sense of the absurd, sometimes foretelling doom in sepulchrous tones...or was that, goofing off in sepulchrous tones and foretelling doom with a Python-esque sense of the absurd? Never mind - why yes, I WOULD like a jelly baby!
KEY EPISODE - The creepy, shape-shifting Zygons (re-appearing this weekend in the Anniversary special) wreak havoc with their pet Loch Ness Monster in "Terror of the Zygons."
PETER DAVISON (Fifth Doctor, 1981-84)
Following the legendary Tom Baker was no easy feat, but Davison brought a youthful charm and vulnerability to the Doctor that was like a breath of fresh air, making him one of the series' most fondly remembered actors.
KEY EPISODE - The Doctor wins the day but loses a friend in the action-packed Cyberman adventure, "Earthshock."
COLIN BAKER (Sixth Doctor, 1984-87)
Brash, colorful and in-your-face, this was a Doctor for the late 80s and he didn't care who knew it. With his insane costume and theatrical speechifying, he was a Doctor who took no prisoners but had a warm, almost cuddly manner beneath the bombast. Though his era on TV was beset by troubles, he's actually become one of the best-loved Doctors thanks to some wonderful scripts from the Big Finish audio dramas.
KEY EPISODE - The Doctor is trapped in the punishment dome on a planet whose biggest export is televised executions in "Vengeance on Varos."
SYLVESTER McCOY (Seventh Doctor, 1987-89)
This eccentric little Scotsman played the Doctor as a terrifyingly powerful being hiding behind the mask of a harmless, bumbling professor. He impressed Peter Jackson so much he cast him as Radagast the Brown in "The Hobbit."
KEY EPISODE - The Doctor is caught in the middle of a Dalek civil war in the 25th Anniversary special "Remembrance of the Daleks."
PAUL McGANN (Eighth Doctor, 1996)
This Doctor embraced life with a poetic flair leavened by a dryly ironic wit, and piloted the most stylish TARDIS ever. He starred in an ill-fated Fox TV Movie, but his Doctor gained new life in the timewarp of spin-off novels and radio dramas, where he became one of the all-time most popular incarnations. He recently made a triumphant return to the screen in a special mini-episode available on YouTube.
KEY EPISODE - The 50th Anniversary Prequel "Night of the Doctor" which shows the final day of the Eighth Doctor and the first moments of...
Stepping in to fill a gap between the old series and new was legendary actor John Hurt (I, Claudius, Alien, The Elephant Man) playing a hitherto unknown incarnation of the Doctor who forswore that name out of shame at what he had to do to fight the horrors of the Time War. But in just two screen appearances, Hurt made an indelible impression, somehow managing to incarnate all the qualities of the classic series Doctor and to give a wry critique of the new boys.
KEY EPISODE - The 50th Anniversary epic "The Day of the Doctor."
CHRISTOPHER ECCLESTON (Ninth Doctor, 2005)
Eccleston had as big a job as Troughton in terms of redefining the role of the Doctor, and pulled it off just as brilliantly with solid acting chops and a goofy grin that only barely hid his war wounds. His was a stripped-down portrayal that made the Doctor a credible character rather than the rather mannered figure he'd become. Other Doctors made us dream, made us laugh, gave us chills - but in one all-too-brief season, his Doctor broke our hearts.
KEY EPISODE - Gas-mask wearing zombies stalk WWII Britain asking "are you my mummy?" in the creep-tastic two-part episode "The Empty Child" / "The Doctor Dances."
This cheeky chappie with the cock-eyed grin and the brooding interior truly was a Doctor for the 21st Century, with a romantic side never before seen in the Doctor's character. He was fun-loving and out for adventure, but don't cross him or he will be your worst nightmare. Indeed, beneath his breezy exterior lay an arrogant over-confidence that came back to bite him more than once.
KEY EPISODE - The Doctor is trapped in time by the sinister Weeping
Angels in "Blink."
MATT SMITH (Eleventh Doctor, 2010-13)
I sincerely love Matt Smith's portrayal. Even if his recent storylines have sometimes left me cold, still I rank him as one of the greats, with his child-like enthusiasm bubbling over and his ancient, haunted soul lurking just beneath the surface. Even after three seasons it feels like we've just scratched the surface of this Doctor, and while I look forward to Capaldi, I feel like I could have happily watched Matt Smith fumble his way to greatness for another few seasons.
KEY EPISODE - The new Doctor becomes the imaginary friend of a little girl who grows up to be the totally awesome Amy Pond - but first, there's the little matter of an escaped alien convict with nothing to lose, in "The Eleventh Hour."
Strictly speaking, he might be the Thirteenth Doctor. Or possibly the First - well, the Second First? The Doctor's future is up in the air but obviously in very good hands with well-respected Scots actor - and lifelong Doctor Who fan - Peter Capaldi taking the helm of the TARDIS this coming fall. We've only gotten a glimpse of this newest Doctor, but it's enough to send shivers down the spine. What type of Doctor will he be? Only time will tell!