I started C25K two years ago in preparation for the Everest Challenge 2011, at 80 pounds overweight and standing 5'1". I just did the regular intervals for C25K. I was by no means fast, but I hadn't planned on winning, I just wanted to finish in the allotted time.
I just went slower than most people doing C25K. I ran at a 3.5-4 and walked at a 3 (during my training). I made sure I listened to my body, I didn't huff and puff while running, I could still carry on a conversation.
I also repeated weeks, Week 3 was rough for me and I know a lot of people say the same thing.
DS15 and I finished the race in roughly 42 minutes, I was beyond thrilled! The adrenaline made me move faster, and it was hard trying to focus on me and not the race everyone else was running but I had a blast and I'm looking forward to doing it again in 2014 with DS11.
I'm down 13 pounds and I'm training for the 1/2 in January.
You can do this!!!!