2007 mini cooper overheating

hello i have never had any problems with my 2007 mini.
it is now at 58k miles, and for about a week now, when i turn off the engine, the fan runs for about 5 minutes. 2 days ago, i noticed the engine oil temp guage went up towards 250 degrees, but no red lights or hazard lights went on. i turned on the heater to cool the engine, and cool air blew out. i cut the engine and coasted, then when i tried to restart the engine…it would not start.
it still will not start. i had it towed to a garage, and it seems to be NOT getting combustion. the fluids were fine….coolant was fine, and the oil was a little low.
BEFORE i have the head gasket replaced, is there any other option, or any safety feature on the car that kicks in to keep the engine from over heating that i should know about?
could it be something simple (read:less expensive) that could be the problem here….
thanks for any information…