You could possibly try refreshing your icon cache.
Go into C:\Documents and Settings\YOUR USER NAME\Local Settings\Application Data\
And delete the "IconCache.db" file. I believe it is hidden, may also be a system file. So make sure you can view hidden and system files through Tools-Folder Options.
XP will automatically recreate this file and rebuild your icons. That may do it. not sure. And you may have to restart.
cheers.