I've been a meathead (and nerd) for over a decade, when people ask me for advice on where to start, I recommend group exercise. If your gym has classes called Body-sculpt/Body-pump/Body-something, try them. It'll be a good mix of strength and cardio... you can build and branch out from there.
http://antranik.org/intermittent-fasting/
btw, I've been practicing IF for 2+ years and love it.