C25K program rocks! If you find some of the runs too easy just stick with it. Pushing too hard too fast can derail your program so its important to follow a schedule (IME).
I too can't wait for winter to be over so that we can run outside. I'm in MA, and its in the mid-40s now, which technically is fine for running but some people's sidewalks still have 2 feet of snow and I don't want to run in the street.
Good luck on your 5k - I want to find one to train for too now!