Not before their insides cook like haggis.
In theory, yes, as microwaves cook from the inside out. Although, the person would be in agony, and probably dead, before it started popping. Think about how long it takes kernels to start popping.. It's very doubtful the person would be conscious by the time they started.
The head will pop
Ew ew ew ew that would hurt. >_<
Yes. Bacon flavoured popcorn.
Yes, but the person will lose interest in the popcorn when he/she experiences the lethal pain ... pain you can't dream of.
No probably not, unless the microwave was stronger than the typical kitchen microwave.