-- Last Updated: Dec-11-12 8:32 AM EST --
You are assuming just a few minutes to walk 100 ft thru extremely chilly water - I live upstate so I know you are talking sub-40 degree water by another couple of weeks of overnight temps in the 20's. That is probably a very good estimate for when the water is warm.
It is not a reliable estimate for when the water is 38 degrees if you have remotely close to my own tolerance - your legs and balance could stop serving you well before you made it to shore in anything less than clothing for immersion. Or if you did make it to shore, you would be unable to help yourself. You are talking about skipping even a wetsuit. In fact trying to re-enter the boat from that 4 or 5 ft of water, a very basic paddling skill which I get the impression you don't have, would take less time thus be safer if executed well. The idea in very cold water is to get out of it as fast as possible. Wading 100 ft to shore is not that.
So far you have expressed a paddling background that finds 2.5 waves challenging and seems focused on swimming or walking out of a capsize rather than handling the issue on the water some way that is faster (thus safer). You are not at a safe point to be paddling alone in dicey weather conditions, and certainly not to assume you can't capsize that boat. You are unlikely to get approval from anyone here for this idea.