Can youstart a turkey cooking and then turn the oven off for a couple of hours then restart?

You could do that but it wouldn't cook your turkey at all. Other than scorching/burning the skin completely off.

Actually your answer is incorrect. My Grandmother cooked her turkey for over 50 years by putting it in a large roasting pan, with a lid. She would then put it in the oven at 500 while she was getting ready for bed. Always at 500 for an hour, then she would turn the oven off. NEVER open the door...the next morning when she got up she knew exactly when to take it out of the oven. The turkey was

THE BEST I have ever eaten. Very moist, VERY moist and juicy the BEST flavored turkey I have ever eaten. She didn't cook the dressing with it, that was done separate using the stock from the turkey.