Delete old “system restore” files??

I run XP Home ed. Have 1 harddisk divided in 3 partitions. After formatting C there are a lot of old “system restore” files left on other 2 partitions, using about 400 mb. Can anyone tell me how to remove those files? The directory they are place in is: \System Volume Information\. Permission to acces this directory is denied, even when logged in as administrator. Turning of System Restore on all drives didn’t help.