Re: Was Hartnell first?
That wasn't the Doctor in The Impossible Astronaut though and the eighth Doctor did say that he might've been dead too long for the regeneration to take place. The sixth Doctor's behavior after the regeneration was chalked up the suddeness of the regeneration.
The greatest science fiction series of all time is
Doctor Who! And I'll take you all on, one-by-one
or all in a bunch to back it up!"
--- Harlan Ellison, from his introduction
to the PINNACLE series of Doctor Who books