The blue smoke you're seeing is probably oil weeping past the valve seals and collecting on the valve heads or piston tops. With almost 200K on the engine, I would expect this as normal wear. Most Escorts didn't live long enough to see the kind of mileage you have. I commend you.
As far as chanding to a synthetic, you've gone this far with what you're using, I wouldn't switch now. Hope this helps
Thursday, April 2nd, 2009 AT 3:34 PM