To go back in time, far along enough on his own timeline, to ensure that his wife didn't die in childbirth. He likely wouldn't use the other two wishes if he could get that.
"Napoleon attacked by rabbits" so I had to go google search it. "The story of Napoleon being "defeated" by rabbits during a hunt in 1807 is a humorous anecdote, but it's not a confirmed historical fact, though it is mentioned in General Thiébault's memoirs. "