William Hartnell was born in St Pancras, London, England in 1908. He was 55 when Doctor Who began, and is still (2011) the oldest of the actors cast in the role. His last appearance (except for archive footage), the 10th anniversary story "The Three Doctors", was made in 1972, when he was 64, and broadcast in 1972-1973. He died in 1975, aged 67. Note: All this information is from the wikia TARDIS Index File article "William Hartnell", so see that for any further details you want.
I'm uncertain what exactly you are asking. He took on the role of the Doctor aged 55. He died aged 67.