I don't know about the jacking up but you should definitely start the car and let it run till it reaches operating temperature with the radiator cap off and the heater on. You should see bubbles coming out and possibly water/coolant, as well, as the bubbles work their way to the top. Keep watching it and if you see the water level drop add more fluid, you can also watch to make sure the fluid is actually circulating through. If you don't see any movement after ten or fifteen minutes of idling you may have a bad water pump, which will definitely cause the overheating you're talking about. Good luck with it.