Where to start on a Dr Who thread. How about the obvious? There's been 10 actors so far who have played The Doctor (not including Richard Hurndall who played the first Doctor in "The Five Doctors"). Here's the order I'd place them from best to worst.
1.
Tom Baker - nothing I can say except he is far and away the best Doctor.
2.
Christopher Eccleston - A pity he only stayed for one year, otherwise he may have challenged for #1.
3.
Jon Pertwee - The first Doctor I watched as a child.
4.
Patrick Troughton - A shame so many of his episodes no longer exist.
5.
David Tennant - I was sceptical when he was cast, but was pleasantly surprised at how good he was. He's been a good Doctor, but I think the time for a change is right.
6.
William Hartnell - The first, yet often most overlooked Doctor. Hampered by the fact his episodes were done "as live" and so any line fumbles were left in.
7.
Peter Davison - The youngest Doctor (until Matt Smith begins his run), he was hampered by the awful production values of John Nathan-Turner.
8.
Colin Baker - I liked his Doctor, but awful stories, costume and JNT production.
9.
Paul McGann - Would have been much higher if he'd done more than one story (and a poor story at that). An excellent actor though, he would have been a good Doctor given the chance. Having only done one story he should have been bottom of the list by default, except for...
10
Sylvester McCoy - I'm still not convinced he was an actor. I remember him prior to Dr Who as a comedian, and doing kids shows like Tiswas, Vision On & Jigsaw. the only actor who I hated in the role of the Doctor and was usually rooting for the aliens in the hope one of them would shoot him and force a regeneration. No surprise when the series was cancelled with him in the role.