your answer is yes. I remember a rep from hashfast saying that there would be overclocking temperature logic built into the chips themselves. They will adjust the hashrate and intensity if a lower temperature is detected. Best believe it makes a lot of sense to mine these in something akin to an icebox or freezer just to get a huge overclock.
Not a good idea.
a) compressors on fridges are small. They are designed to keep cold stuff cold not remove a 1.2KW heat load.
b) cooling below dew point = condensation onto components which probably don't enjoy getting wet.