I have avast home edition, XP Dell Dimension c521.
Recently I get his by some virus and I needed to get rid of it. Avast only sat and still sits on scanning status 1%. 
I got rid of the virus/trojan via trend pc cillin but I would still like to use avast. It has been working for over a year for me. I tried leaving my computer on all night with the avast running and it still was stuck on 1% scanning status. >:( Usually is take 1.25 hours to scan my entire hard disk. I’m afraid to delete avast and reinstall - any directions SOON will be greatly appreciated! 
A number of us were hit by a stuck solid scan when we were using the avast update 090109-0.
The avast team have taken care of the problem in the 090110-0 update. So before looking for any other cause it would be best to ensure that avast is up to date with today’s update and try the scan again.
; Yeah it’s working again - very scary since it happened right after I got hit with a trojan. thanks!!!
Well if you have learned anything it is quickly seek help on the forums ;D
Welcome to the forums.