Ok, to you and anybody interested, what if it were you and one other person.
Well, I hate to keep "missing the point" of your thought experiment, but one other person does not a society make. I doubt I would even be able to follow HYP86's advice, on setting about to repopulate, except that I would probably feel some sense of duty to do so.
Given that I've already answered, I'll try again. If it is myself alone, or myself and one other person, with all of the knowledge and tools I could want-- even if I had to build them myself-- then my first task would be to create other sentient life; I could survive, even as a lonely god, if I had at least that much of a place in society. Assuming there were chimpanzees left, I might try uplifting them without genetic interference, to test some of my current theories about the development of society and the evolution of humanity. Or I might terraform a couple of planets and experiment with different sentient species designs. Might even try recreating humanity, and scattering it across the galaxy; it would be fun to see them try to figure out how they evolved concurrently on different worlds.
Would probably also dedicate considerable time to spiritual exercises, and see if I couldn't eventually leave this plane of existence and explore Yggrdrasil's branches. Go bother the gods awhile, if they weren't also missing and/or upset with me over what happened to the rest of my species. See how much I could learn to affect my surroundings without tools.
Of course, with another person involved, I am certain that we could use all of the technology at our disposal to come up with some truly elaborate games.