To replace my rotors I used a 17mm 6 point socket and a Craftsmen 1/2 drive breaker bar. Depending on which side I was doing I had to grab the car with one or two hands and push on the bar with my foot. If you have time you may want to try soaking them for a few days with PB Blaster (best penetrant around) and then try. I'd avoid heating them if at all possible. I also don't own any pneumatic tools and have managed to take most stuff on the car apart without them.

Good luck.