Thanks for the 2 replies.
I DO NOT use the shut down button from the Charm bar on Windows 8. It is a stupid feature of Windows 8 to take 4 steps/clicks to shut down a computer [1) move cursor/swipe right side of screen to bring up Charm bar, 2) click Settings, 3) Click Power, then click Shut Down.] So lame!
I use the normal shut down method by clicking the Start button and then Shut Down (2 clicks only).
Anyway, Norton should fix this On Demand Scan hanging problem because they have a responsibilty to fix a faulty software they have sold to their customers.