Yellow, you are right. I want to love running and in my head I picture myself being strong running, but once I get out there, it's mostly a no-go. And when i do run faster or further than usual, I pay for it for the next few days. I have some physical issues with cycling, too, but it never stops me from riding; in fact I can often achieve a good average for me when i start off feeling like crap. I really don't have any expectations of speed or mileage, though, when I run. It's just, with cycling, I had a steady improvement for a few years, until I realized I was driving myself nuts trying to get faster and now I am much more relaxed about it. But, I never had that ramp up with running. I had one spring and one fall where I steadily improved, but then either cycling or winter sports took over. It just pisses me off; I see others who look much more out of shape than me become "runners," and I just don't seem to have it.
What's a pro-con list? Pardon for being ignorant...