I am 1 day into starting the "couch to 5k" plan.  It is a 9 week plan to get from where I am now to successfully completing a 5k.  I did day 1day and found that it wasn't "too painful."   After my Day 1 experience, I can say without any hesitation, "I am no runner!"  But I am going to keep it up and see what happens.  

Here is a link to the basic plan http://www.c25k.com/ .  There is this awesome mp3 I downloaded that just tells me when to run and walk with music already set up and ready to go.  Here's the link for that.
http://www.c25k.com/podcasts.htm.

I am determined and will get it done!