coolant in your oil, oil in your coolant, oil/coolant leaks around the head is what I know about blown head gaskets.
One quick check you can do - while engine is COLD, take the rad cap off. start the engine and let it warm up. Look into the rad and watch for bubbles. the bubbles are the exaust gasses leaking into the water jacket, and means your head gasket is sick.
What is the color of the smoke? Blue means it's burning oil. White means it burning water or it's condensation from exhaust meeting cold air.