Of everything you listed the incubator is most at risk. The snakes can survive for a while at room ambient if you can maintain 75*F. I wouldn't feed until after the storm passes; if the power goes out then empty snake bellies are a good thing.
The problem with the incubator is that digital thermostats may not "like" generator power as it can be dirty, so make sure you have a surge protector between the generator and the thermostat, and check it constantly.
Personally we have a backup generator that powers the wood stove blower so the house stays warm, and we moved a cord of firewood into the garage last night so we won't have to dig it out of the snow - one forecast has us getting 45 inches of the stuff! At least I won't have to worry about keeping the refrigerator and freezers running, Mother Nature is taking care of that.