Team Hartnell with 25 degrees of separation, although I'm really Team Tennant at heart! ;)
EDIT: confirmed all the connections.
William Hartnell
1 Heather McIntyre (his wife)
2 Thomas McIntyre (her father)
3 Mary McIntyre (his sister)
4 George Harmsworth (her husband)
5 Jack Harmsworth (his brother)
6 John Harmsworth (his son)
7 Mora Kelly (his wife)
8. Patrick Kelly (her father)
9 Kate Kelly (his sister)
10 John Emmett (her husband)
11 John George Cheere Emmett (his father)
12 William Thomas Lawson Emmett (his brother
13 Frances McMaster (his wife)
14 David McMaster (her brother)
15 Joseph McMaster (his son)
16 Maud Eliza McMaster (his daughter)
17 Joseph Atkins (her husband)
18 John Arnold Atkins (his father)
19 James Atkins (his father)
20 Joseph Atkins (his brother)
21 James Atkins (his son)
22 Charles Atkins (his son)
23 My Grandfather (private)
24 My Mother (private)
25 ME! :)