Hi Little Bird, What everyone is trying to tell you is that you should sit there for a few minutes, and keep an eye on those things to see which files keep repeating themselves in the scanner.
It could be something like an automatic updater that is blocked from accessing the internet by your firewall, and it just keeps trying to get out repeatedly.
I have avast! set in "Paranoid Mode," and I also have it set so that all of those aggravating little information bars are always running at the bottom of my screen just so that I can get an idea of what my PC is doing.
I had a similar experience to the one that you are having, and I was able to fix my problem just by seeing those files being scanned over, and over repeatedly.
So it might work for you too Boo! ♥ Wendy