Definitely the resistor.
One thing to think about, it *****, but it's what I was told, is to replace the resistor and the blower motor at the same time. I did this because I was told that there is usually something that causes the resistor to go, and if you put a new one in there, it might just get blown again. I'm not sure if it's 100% accurate, but since I was already in there changing the resistor, I went ahead and changed the blower motor as well. It's a little more money, but I'd be pissed if I changed the resistor and then had to buy another, plus the motor, plus change it out again. Just FYI of what I was told/did.