I don't think it will inhibit hair growth as I have never heard about its success in this area but cider vinegar can actually address other skin problems, particularly acneic breakouts. The antioxidants in cider vinegar protect from free radicals and bacterial infection. No, do not heat up the vinegar.
If you want to use cider vinegar, dilute it. Use 1 part cider vinegar to 5 parts of water and then, once you get used to it, your ratio can change to 1 part vinegar to 4 parts water and then, 1:3 ratio, and finally, if your skin is fine with it, you can finally use a 50% - 50% solution.