2 hours seems like a reasonable goal. You might want to try to find a local 5k and 10k to run as part of your training. It will let you test your progress, try out eating before and during the race, get used to holding your pace in a large crowd, etc. You don't want any surprises on race day.
As the race gets closer try to do some running each week at your goal race pace.
At a 2 hour pace with low training volume you might want to experiment with some sort of run / walk pacing scheme. Jeff Galloway has had a lot of success coaching in this manner:
At 9 min/ mile he recommends roughly 4 minutes of running with 1 minute of walking. Actually, I think Greg A would have completed the 100 miles with some sort of run/ walk, or maybe even run/sit pacing.