The virus has apparently infected your System Restore folder.
You'll need to turn-off System Restore, reboot, then turn it back on.
One cannot delete an individual Restore Point....it's all or nothing.
How to Turn On and Turn Off System Restore in Windows XP
http://support.microsoft.com/default.aspx?scid=kb;en-us;310405&Product=winxp
--
Carey Frisch
Microsoft MVP
Windows XP - Shell/User
Be Smart! Protect your PC!
http://www.microsoft.com/security/protect/
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|I have a netskey infected file in the folder c:\system
| volume information. However access is denied to get into
| the folder, either manually or with a virus program. How
| do I do it?