I have installed about 20 Microsoft security related
patches and I when I was asked to restart the system
(Windows 2000 server) it came back but I am unable to
logon. When I try to logon (enter administrator and its
password) I get a sky blue background with a cursor only
(even if I wait for 1/2 hour).

I tried rebooting with last good know state, safe mode and
safe mode with networking and I get nowhere either.

Can anyone help? Is it possible to roll back those
patches? The effect of those patches are worst than a
bloody virus.