I am making chocolate treats with mini Presley's caramel and chocolate. Can I use a regular Hershey's bar or use baking chocolate or can I mix them to make a harder coating or will the regular harden?
There are certain kinds of chocolate that are formulated for coating. Couverture is one of the names. My local grocery store has discs of chocolate that come in packages that are meant for this. Here's a link to a good explanation of the differences. http://gourmetcandymaker.com/select-the-best-chocolate/
Any couverture or compound chocolate (milk, dark or white) will work fine. Compound is cheaper and easier to work with, whereas couverture is the real deal and requires tempering if you want a glossy/snap finish. Feel free to use buttons, chunks, chips or whatever you can find.
Careful not to burn either. I generally microwave my chocolate at 50% power level for 45 second intervals to desired temperature or just to melt (depending on the application). Safest way is a double boiler.