Unless the microwave oven is severely damaged, the shielding should prevent any "leakage" so it's probably just psychological. If you somehow manage to remove the door and still keep it running, though, things get fun.

"fun"? :-0

Using the Dwarf Fortress definition of "fun" there. http://dwarffortresswiki.org/index.php/Fun

You should probably replace that oven ASAP, or get rid of it completely to be a retro hipster. :)

I don't have a microwave at home. I cook and freeze batched. use the oven at work.