Caution do this with care
You can access system volume information by doing the following on XP Pro, not got the home version to check if you can do this or not.
Scroll down list and untick Use simple file sharing
Now right click on system volume information
Type in your user name
Now make sure you tick:
You will now be able to access the content of this folder.WARNING this information is to do with system restore my advice is once you have removed the offending file if it is a virus, undo what you have just done to stop accidental deletion.
However before removing the file, go onto the web go here http://virusscan.jotti.org/
, stop AVG and upload the suspect file here to check it is a virus. Don't forget to restart AVG as soon as the file is uploaded.