Originally Posted by Orangecicle
New head gaskets require a resurfacing of the heads to do it properly. It can be done without replacing rings if you are careful and leave the piston heads in the cylinders. Some mechanics just pull the cylinders off of the pistons, and then you need new rings.
New rings are only needed if the old ones are worn; you can check ring gap for that. That said, if you have high mileage, it's usually a good idea to replace them because they can lose their tension after (quite) a while. The heads/jugs don't need to be resurfaced unless something is warped or has some fairly severe surface damage to it. I think people have a little bit of a misconception when it comes to how delicate a head gasket is, and how perfect everything actually needs to be, this coming from experience as being a mechanic.