Perhaps something here will help:

http://support.microsoft.com/default.aspx?scid=kb;EN-US;302796

I'm guessing you had an improper shutdown or possibly a virus which might have corrupted SR. If the points prior to yesterday are corrupt XP will not let you 'roll back' to them as Denny mentioned on the other board. If you haven't used Cleanup/Advanced, and I assume you haven't, it's highly unlikely you will be able to go back prior to yesterday. You should try to revert to yesterday just to see if SR works at all; you can "Undo" that process if it does work. If you know what you/other did wrong or you're getting an error message share it so we can help. I would suggest you download and run this utility; you may have to re-install some Windows updates.

http://belarc.com/free_download.html

PS It's possible this is a Windows problem but  even if it is it's highly unlikely the damage to your restore points can be undone.

Sounds good. This MS download complements the Belarc utility. Run them both after installing or un-installing any Windows updates.

http://support.microsoft.com/default.aspx?scid=kb;EN-US;q282784

Thanks for your suggestion. things seem to have worked out.

Thank you for your suggestions. that utility will come in handy. my problem was with another program which reinstalled, and its okay. i disabled system restore and i think its okay since i enabled it again. Thanks again

thank you for your continued help. i downloaded and ran the second utility, but it only lists windows 98 updates. whats wrong?

I don't know. Do you have a dual-boot setup with XP and 98 ? Did you download the XP/32 bit version of qfecheck to System32 folder, install and run (the command): qfecheck
from the Command Prompt ? That's how to do it.