Installing Update hangs

When attempting a shut down I am presented with the usual message not to
turn off computer. The System is now hung on "Installing update 1 of 24".
The computer has been in this state for several hours and I have no idea
what to do. I have searched for a solution but have not seen any resolution.
I am using WinXP Pro SP 2 on a 2.8 Ghz System. Can anyone off a safe
solution? What would happen if I turn off at this time?

Thanks.

Jake


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