Try this at your own risk:
Disable System Restore on D:
Then gain access to your System Restore Folder:
http://support.microsoft.com/default...;en-us;309531&
Then delete the System Restore folder on your D:
try running defrag now, reboot if you want before this.
Reenable System Restore on D: and it will re-create the system restore folder with the permissions turned off again to protect the folder.