I'd start doing some homework on this site:
http://ball-pythons.net/forums/index.php. I'm sure there are others as well, but as a BP owner, this is the best i've found so far.
Yes, lose the heat rock! An uder tank heater (UTH) is the best. Various types from heat pads to fex watt tape. I'm currently using the heat pads from the pet store. One on the warm side controlled by a rehostat. Eventually i'm going to build a rack system and use the flex watt heat tape and a t-stat.
At his age, I'd think 2 or 3 weeks with an adult rat would be fine. But I'm only familar with young ones so far... Check the site I listed... Frozen\Thawed rat should be the food of choice though. Keep it in the freezer until the a day or 2 before freeding. Put in fridge to thaw as you would meat. Then when ready, place in a dish of warm\hot tap water for a good 20mins (in a zip lock baggie), changing out the water when it cools. You want to serve it warm to the touch and be sure the insides have thawed...
You generally know if they are hungry becuase they will get active when smelling the rat. But don't worry if they reject it. Just take it out after a few hours else it will get rancid (and trash it). Wait a week and try another one. It is fairly common for a BP and other snakes to go several months without eating. They can go off feeding for a number of reasons: health issues, mites, shedding cycle, stress, or just because... With good husbandry, you can be confident that things are fine and that he'll eat when ready...
A glass display tank is not the best for BPs. They are shy and like to hide and privacy. They can stress if on display and don't feel secure. Offer a hide on the warm side and a matching hide on the cool side so he can thermoregulate as needed. If in a glass tank, adding fake plants can help him feel more secure and comfy moving around from one hide to the other.
A bowl of fresh water can be provided. Just change and clean it often. If he is soaking in it often, he could have mites. You typically should rarely seem him in it...
Get a good digitial thermometer\hygrometer combo. You need to know the basking spot temp (under the warm side hide on top of the heat pad) and then on the cool end. Humidity is important as well. A screen top will make managing this very difficult. I have tips for dealing with this if needed...
For handling, a BP is about as social and tame as any snake can be. But only in moderation. Like I said, they like their privacy. Let him rest about a week when you first get him. Then once a day, for 10 mins is pretty good. Once a week is OK too. But during shed i'd leave him alone (watch for the eyes to glaze and kinda turn blueish) and leave him alone for a day or 2 after eating.
Once you have the basics down, they are very easy to care for and rewarding pets. But the basics ARE vital. Check the good caresheets offered on that site.... :study: