A couple of words on calibration. You are better off calibrating at a point that is closer to your usage point. So for instance, it's better to calibrate at boiling than in ice because on your 'que you are usually measuring temperatures closer to 212F than 32F.
I calibrate the thermocouples in my lab by using a mercury in glass thermometer of some quality. They stay pretty accurate and can be a good investment if you need to be sure. I boil water, stick in the glass thermometer and then stick in the probe and calibrate the probe to the reading off the glass.
