I just installed Windows XP Pro fresh on a computer and towards the end, I installed Avast 5.0 Pro. Every time I open up "My Computer" or Windows Explorer, the floppy drive is accessed and frequently the icons on the desktop disappear and then come back. There is a big delay going on.
I did try turning off those two settings in the "Files System Shield" -> "Expert Settings" -> "Scan when Attaching", it made no difference.
Previously this computer had been using 4.8 and upgrade to 5.0 without the problem. Then the Hard Drive died and I installed a new one and re-loaded Windows XP and the software.