Trojans in archived System Volume Information\_restore…

I NEED HELP!! My friend’s computer has 46 infected files that have been archived in System Volume Information\_restore files(?). I turned off the System Restore option to remove all restore points but some have been archived and avast! Anti-virus program finds the Trojans in the archived files. I can’t find the archived files and can’t delete or move them in avast!; I get an error message saying it is not supported. Are these going to creep back in and create havoc again? How can I find the archived system restore files to delete them? I’m going insane trying to remove these files!