William Hartnell during his time as the Doctor.
The 1st Doctor:
William HartnellThe 1st Doctor lasted 3 full seasons, and 2 out of 9 stories of the 4th season, before he was forced to retire due to ill health. His stories are noted for their historical accuracy, and that a lot of them no longer exist! (This is because of the BBC's policy of reusing old film disks to save space and money) Those that are gone include: The Dalek Master Plan, Marco Polo, The Savages and the all-important final episode of the Tenth Planet, where the Doctor regenerates for the 1st time. Many regard William Hartnell as being the definitive Doctor, and whilst his acting was very good, he did fluff his lines every so often, mainly because scenes were usually shot in just one take. William returned as the Doctor in the 10th Anniversary programme: The Three Doctors, with Richard Hurndel reprising the role for the 20th Anniversary programme: The Five Doctors.
Hartnell is my least favourite Doctor- but that isn't to say I don't like him! He makes a good Doctor, but is too aloof for me. They say things get better with time, and they did, but they started off highly!