I think that you could get a decent yield from that setup. The problem is obviously the height of the growroom, but that can be overcome by using SCROG (screen of green, read about it on Overgrow.com, in the FAQ). I have no idea where you could get a thermostat that would work with the fridge but the fans should be enough to keep the temperature down.
You should really try to squeese in a couple of extra fluoros. The more light the more yield.
Also, put a lock on the fridge (just to be safe) 