>>im afraid this means disconnecting the propane, which im sad to say is
almost completely full currently. (can you purge it yourself, or should
a shop do this?)

Chris,
Turn off the valve on the propane tank.  Light your stove and let it run until it goes out.  There is now no propane in the copper tubing that feeds the fridge an stove.  It will now be safe to remove the fridge.  Follow the copper line from the fridge back toward the tank and remove it and cap it off.  
We use our fridge all the time and I think it works OK.  I would clean and repair your fridge and re-install it.  If nothing else a working fridge will help with resale value if you ever want to sell your van.
George
'85 Westfalia