Originally Posted by
Steward Denethor II
In theory you could, but I couldn't imagine taking that long to complete one campaign as one turn is two weeks. If it was on medium or easy you would get super bored as the AI would just sit there, while if you were on hard or very hard they would attack you unrelentingly, forcing you to crush them.
As for the second question, I don't know, I have never seen anyone die of old age in Napoleon but I would assume its possible. But I know Kings don't die in battle, and only Napoleon fights in them.