they sell temp control that your freezer plugs into, and a probe that you hang inside the freezer. see the link for some examples Austin Homebrew Supply
i don't insulate the holes. if i remember correctly the OD of the shank is just under 7/8", so i used a hole saw for 7/8". there is hardly any space around it to even try to insulate.
i only have the keezer set up and i love it. i have room for 5 kegs (tight fit, but they will). i installed 4 taps and its a nice set up. depending on how strong you are it could be a pain to lift 5 gallons up over wood collar. Search around BobbyM (i think i have that name right) attached his collar to the top. its so nice not bottling anymore.