-- Last Updated: Dec-08-12 8:02 PM EST --
I have occasionally stirred up trouble with one or two people here by suggesting that one does not "necessarily" need a wetsuit or drysuit for paddling small, quiet rivers in fall or spring when the water is cold. Getting out of the water in such a situation normally doesn't take long (but it COULD take too long in certain cases, so being prepared for the worst is still highly recommended). However, I'd never say that about paddling lakes when the water is cold, especially not in winter (even the colder temperature of winter on tiny rivers would make me really nervous about not being well prepared for spending some time in the water). Besides, even with the best safety intentions, a lake paddler isn't likely to be nearly as close to shore as someone on a little river, and in a lake you are far less likely to be able to get your feet on the bottom anytime soon after a capsize either. Best to be prepared for the worst.
I've never heard anyone say wetsuits are designed to work wet and not when dry. The usual complaint I hear is that they tend to be too warm until they get soaked. But if yours won't keep you warm when it's dry, wear something over it for additional insulation and to block the wind. I think the comfort issue is something you can get used to, but if not, a better option would be to find something that is comfortable, and wear it.
All the other advice so far, I agree with. Personally, I normally wear a drysuit for boating on lakes when the water is cold, and frequently wear it for quiet rivers too.
By the way, I'm assuming your lake is a deep one, since wave action won't keep any lake open all winter. In fact, constant wave action will make the day of freeze-up arrive sooner. You see, a lake won't freeze until some time AFTER the whole water profile cools to the temperature of its greatest density (about 39 degrees F). As water at the surface cools, it gets more dense and sinks, until eventually the lake gets filled from bottom to top with water having the temperature providing the greatest density. Once the whole profile from bottom to top reaches 39 degrees, water at the surface which cools further becomes less dense and "floats", where it stays exposed to the colder air and eventually cools below the freezing point. This process takes much longer in a deep lake than a shallow one, and if the lake is deep enough, it takes longer than the duration of the winter season so freezing never happens. Even huge, cold-exposed and wind-swept Lake Superior would freeze quite quickly each winter if it were as shallow as Lake Erie.