If I can offer some advise I would say start slowly with the purpose of conditioning but not to give too much pain and discomfort.
A little pain is to be expected, but don't over stress your self to a point that you get discouraged and drop out.
Set a defined program on a week to week basis within your distance and pace and on your comfort and conditioning level.
For beginning runners I strongly recommend purchasing the most cushioning pair of runners you can find that will fit your feet,
your feet and knees will thank you for that in the long run ( no pun intended )
Even wearing thick sport socks is a good idea also , if you haven't been doing any road work your legs and feet will feel less pain if you pay attention to what your
putting on them.
The key to a successful conditioning program is to progress slowly with set goals, if your distance you feel is not enough then increase it, if you think your distance
is too much then back it off a little and don't forget to take a day off to rest and recuperate, but keep in mind to keep your program constant so that
you can progress and make the important health gains.
One of the advantages of running is that it increases your metabolism and therefore this will cause you to loose weight, at the same time will strengthen your
lower body from your shoulders down.
Another plus is when running distances your brain releases endorphins that make you feel good and therefore puts you in a good mood, this is often called the
runners high, imagine that a high that you can obtain without having to take any drugs or booze, what a concept, and at the same time doing
something to benefit your health and not diminish it.
Good luck and good health to you,
After saying that I think I better get off my ass and go for a run