I actually ran last night. Well, jogged. In the dark, where no one could see me, so you'll have to take my word for it, but yes, I jogged and I live to tell the tale.
I'm following Theresa's advice (which is based on advice in the Beginning Runner's Handbook) and doing 4 minutes of brisk walking alternated with 1 minute steady jogging. It didn't seem as if I were doing enough. I kept thinking I should stop playing it cautious and just go do my imitation of a sprinter. Somewhere in the back of my mind is the idea that if I run faster I will get it over with sooner. (The back of my mind is not a place to go if you're looking for logic.)
Safety disclaimer: The park where I jog has lights, so it wasn't actually in the dark as such, and it's a quiet nothing-ever-happens-here place surrounded by townhouses and apartments. In other words, I feel safe jogging there in the evening. If it ever starts to feel iffy, my neighbors would gladly loan me their dog for the jaunt.