BMW Repair: BMW Blown up or what., piston rings, pcv system

Question
2002 bmw. I started my bmw (it was -10) and drove it about 2 miles and noticed white smoke coming from the exhaust. I then turned left to get on the interstate and motor killed. I noticed oil under vehicle and had towed. I tried 1 time to turn it over and it was like it was stuck. I had it at the dealership and they said the motor was stuck and would not turn over. I brought it home its been sitting 2 yearr. Yesturday I went to move it and it started right up. It sounded excellant but still smokes. Doing research I found the symptoms all relate to CCV/PCV problem. I wonder why the car would not turn over like it was stuck and then start all of the sudden? I looked into the exhaust and it has no oil in it but only on the outside. I took the valve cover off and looked inside by the cranks and there had been moisture in there. I took spark plugs out and they are fowled looking but none soaked with oil which I expected one to be (thinking a bad ring or something was the cause). From the way the car sounded it was not a piston/rings/rods. As I previously stated I think the CCV/PCV blew because of freezing. I still cannot figure why the motor seized and then restarted though. Your thoughts and am I on the right track?

Answer
You didn't mention the model of your BMW but I'm thinking you have is 3 series with a M52 engine.There is an issue with the PCV system.You have experienced all the symtoms.BMW does know about this and have a kit available.What happens is the PCV system gets plugged up over time due to condensation built up in the oil separator, the engine,designed as a closed system(no PCV Valve)needs to have an internal flow.Age and oil changes,oils(syn or not) cause wear and the separator plugs up or hoses collapse.The white smoke was cause by oil being drawn in from the crankcase, you hydraulic your motor (oil on top of piston).The oil bled down and the motor turned over.
Call your dealer they have the kits available.If you do it yourself you need to be experienced,its no back yard fix.Cost about $900