PC wont shutdown

Boot up and go into the BIOS, press the key, F1, F2, DEL, F10, depending on your set up.
When in look for "load default settings" and select it and re-boot, let it load up Windows and then do a full Shutdown. Wait 15 Minutes and then boot up as normal.

Please post back if you have any more problems or questions.
If this information is useful, please mark as helpful. Thanks.

Check your Event Logs and Minidump files

Windows XP restarts unexpectedly or restarts when you shut down the computer

http://support.microsoft.com/kb/320299/

Minidump Files can be found here. C:\WINDOWS\Minidump\Mini122707-02.dmp

How to read the small memory dump files that Windows creates for debugging

http://support.microsoft.com/kb/315263

To download and install the Windows debugging tools, visit the following Microsoft Web site:

http://www.microsoft.com/whdc/devtools/debugging/default.mspx

Instructions on using Windbg.

Open Windbg and select file, Symbol file path and brows to the Symbol folder that you have downloaded and installed Symbols to, select OK.

Close the workpage and save the Workspace information. This should lock in the Symbol path.

Open Windbg and select file and select Open Crash Dump then navigate to the minidump, highlight it and select Open.

There are two ways to use !analyze -v the easiest is to click on !analyze -v under Bugcheck Analysis.

When you have ran the initial dump if you look to the bottom of the screen you will see kd> to the right of that type in !analyze -v and press the Enter key.

Ctrl + a will let you copy the information and paste it into notepad.

Look to the bottom of the page for information like this. This was fixed by updating the Graphics Drivers.

FAULTING_THREAD: 864f6a98

DEFAULT_BUCKET_ID: GRAPHICS_DRIVER_FAULT

CUSTOMER_CRASH_COUNT: 1

BUGCHECK_STR: 0xEA

PROCESS_NAME: logon.scr

LAST_CONTROL_TRANSFER: from 00000000 to bfef0fea

STACK_TEXT: f6434e6c 00000000 00000000 00000000 00000000 sgiul50!DrvBitBlt+0x585

STACK_COMMAND: .thread 0xffffffff864f6a98 ; kb

FOLLOWUP_IP: sgiul50!DrvBitBlt+585 bfef0fea 75f9 jne sgiul50!DrvBitBlt+0x580 (bfef0fe5)

SYMBOL_STACK_INDEX: 0

SYMBOL_NAME: sgiul50!DrvBitBlt+585

FOLLOWUP_NAME: MachineOwner

MODULE_NAME: sgiul50

IMAGE_NAME: sgiul50.dll

DEBUG_FLR_IMAGE_TIMESTAMP: 3b7dfec7

FAILURE_BUCKET_ID: 0xEA_IMAGE_sgiul50.dll_DATE_2001_08_18

BUCKET_ID: 0xEA_IMAGE_sgiul50.dll_DATE_2001_08_18

A couple more tips here

http://www.kellys-korner-xp.com/win_xp_restart.htm

Keep us informed as to your progress if you require further assistance.

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