How to develop a habit of regularly working out and stay motivated?

The question pretty much says it all - but here's some additional information concerning my situation.

I'm not at all athletic, but not obese or anything. I would like to lose about ten pounds, and then just continue to improve my health. I also don't have any athletic experiences. I'm eating acceptably, but not super-healthy either and have no desire to end up having diabetes or some sort of heart problems, which is why I want to start doing something now rather than once it's too late.

When I was a child I couldn't do any sports that put a strain on my knees due to a chronic disease, and when I was well enough to start sports I had already found other interests. Today, sports bore me. I would like to run, since I like to take long walks, but whenever I start I get incredibly bored after just ten minutes. I tried listening to music, but then I can't keep running (my physical feeling is a little off, I'm also a really bad dancer) and I can't think of anything either, because then I'll trip or run into passers-by.

Other than that, I'm not exactly strong (muscle-wise) and get out of breath quickly, but I suppose that's going to improve. My main problem is really the interest. Whenever I tell myself that it'd be a good time to go out and run a little, I already know that it will be such a dull activity that I'm much more tempted to do things I love and read something interesting, or study. Joining a team isn't an option right now either. I don't know a lot people here and I'm also not sufficiently trained to keep up with others. I'd be way behind everybody else and just not confident enough to do something I suck at with a bunch of people I don't know.

I'd be happy about every bit of advice!