Sounds like the first thing for you is to go outside.- No need to change the treadmill blindspot.-
There are loads of training plans out there.-
Build up slowly and run at a far slower pace than you expect( It's not run for the bus running, you should just about be able to hold a conversation).
Run walk works well for lots of people,- between lampposts or for timed segments is usually the way it's done.-
generally, just get out there and do a bit.- but try not to leave yourself broken for days afterward and don't push yourself so hard that you dread your training runs or you'll stop...
I also agree so much with the park run for motivation and finding people at a similar level to you.
Oh, and once you're sure this is something you're going to keep up to ( or the moment you start getting twinges in feet/shins/knees) get yourself to a proper running shop ( think runners need not JJB sports) and get some shoes that suit your gait.