After sitting at idle for more than 10 mins I get a big cloud of blue smoke when accelerating. I understand I likely have worn rings. The car has high mileage. Just wondering if there is a safe product to add to the oil to reduce the oil burn?

 

How many miles on the engine? In my experience, your situation sounds like a failing PCV system. You can either try to fix the PCV valve, or replace the cam cover. Will be much less expensive than an engine rebuild.

 

PCV or valve stem seals in my guess. Valve cover is the easy thing change first.