Do you have Spybot's Teatimer running? If so, you should try making the changes to your settings after disabling Teatimer. The instructions for how to do that can be found at http://forums.spybot.info/showthread.php?t=2827
Also, have you tried returning your computer to an earlier restore point from before this problem started?
If you've never done this before, Go to Start / All Programs / Accessories / System Tools / System Restore
check the box to Restore my computer to an earlier time
and click on Next
. You'll see a calendar with highlighted dates. Choose one of the dates just preceeding these problems and allow your system to return to that date. See if the problem goes away.
If this doesn't work, go back into System Restore as per the above instructions, only this time choose the option to reverse the change you made.
Did either of these work?