Stop putting tin foil over the things you heat up in there

...all I wanted to do is make some old style Jiffy Pop. What, I wasn't doing it right?

If the microwave is blowing, then it is faulty.
FYI, you have a 20 Amp breaker with 10 kA AIR (http://wiki.answers.com/Q/What_does_the_ka_rating_of_a_circuit_breaker_mean).
Vito
Ahh, thank you. That's re-assuring and frightening at the same time it was shooting out that much electricity to trip the breaker. It did cook the food pretty thoroughly though when it worked.
Thank you guys. I'm heading out to the store to return this for something similar, but maybe a bit better quality. Although this one is a Kenmore...