Dave, I dont think people will judge you as much as you think. I am overweight and have got stuck into the C25K program ( currently on week 3 day 2) and already feeling the benefits. I found that I get a friendly nod from other runners. Before I started to run I had imagined that all runners were super slick and could run for miles, yes they are out there BUT there are loads of us fattys putting in the miles too.
The only barrier I have found with C25K is that your mid will say "jog for 90 seconds, I dont think so !!" but after doing the runs, you WILL look back with pride and realise that it was never as hard as your mind thought it would be.
REMEMBER: DEAD LAST is better than NOT FINISHING. NOT FINISHING beats NOT STARTING. Good luck
There are quite a few out there, I'm currently using "simple C25K" very basic but very good also. From this I'm going to use "simple C210K". they are both by the same guy and both free.I should also mention that these are found on google play for android, not sure if it supports other platforms.