Evidently it's caused by a damaged registry. Try to restore system.da0 as instructed in the "how to troubleshoot registry" link. If that doesn't work try system.1st.
http://support.microsoft.com/support/kb/articles/q145/8/36.asp
Will a startup disk with cd-rom support allow you to run the restore disk?
http://support.microsoft.com/support/kb/articles/q145/8/36.asp
Will a startup disk with cd-rom support allow you to run the restore disk?