which I'll leave to others to explore. You can in mean time, run a Checkdisk R(epair) automatically which should correct any system file errors & repair any damaged areas on the HD disk. This may well solve no shut down status. Worth a try & can't hurt!! Here's how:
Disk/repair (Check Disk) (like SFC)
Left click on My Computer(open)
Right click on "C" or your OS drive if another letter.
Left click Properties and then click Tools Tab.
Left click on "Error Checking"> Check Now.
Left click to enter check mark in BOTH boxes offered.
Left click on "Start".
Computer will have to reboot to begin repairs.
Just leave alone (you're locked out anyway) 'til process finished.
In regular mode will take about 1 Hour (more/less)
In Safe Mode about 2 hours.
If computer normal after process complete you might want to create a new
restore point and Label it POST ERROR REPAIR.
This is based on using an onboard copy of sys
files if copy is ok.
If copy is corrupted, it may tell you to insert XP or SP2/SP3(if patch applied) disk or to indicate location of SP2/3 info to get new,
clean copy inserted. Good to have disk at hand. Good Luck!! 
Good day or night,
Earlier today I got a nasty trojan off my computer. And now XP won't shutdown. The shutdown process begins, icons and taskbar disappear, and then it stops, nothing on the screen but my desktop image. The thing even goes into sleep mode this way. But no shutdown.
I have tried some standard troubleshooting. Updated to SP3, updated Dell BIOS (have Vostro 1400). No luck.
Could this have been damage caused by the trojan? Several trojans were removed during safe mode by Malewarebytes [only log with removal info below]. The log means little to me. Not sure if I had a zlob.g, zlob.d or a win32.zafi.b. A fake "windows security alert" was coming up warning about a "win32.zafi.b" and then mozilla stopped working and IE took me to a "safe soft review" website and then shut down.
Anyone have any suggestions? Anything appreciated...
Anthonology
=============================================
Malwarebytes' Anti-Malware 1.30
Database version: 1321
Windows 5.1.2600 Service Pack 2
26/12/2008 2:07:22 AM
mbam-log-2008-12-26 (02-07-22).txt
Scan type: Full Scan (C:\|)
Objects scanned: 112020
Time elapsed: 51 minute(s), 35 second(s)
Memory Processes Infected: 1
Memory Modules Infected: 0
Registry Keys Infected: 3
Registry Values Infected: 2
Registry Data Items Infected: 1
Folders Infected: 2
Files Infected: 5
Memory Processes Infected:
C:\WINDOWS\system32\drivers\svchost.exe (Heuristics.Reserved.Word.Exploit) -> Unloaded process successfully.
Memory Modules Infected:
(No malicious items detected)
Registry Keys Infected:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\msupdate (Rootkit.Agent) -> Quarantined and deleted successfully.
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\msupdate (Rootkit.Agent) -> Quarantined and deleted successfully.
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet003\Services\msupdate (Rootkit.Agent) -> Quarantined and deleted successfully.
Registry Values Infected:
HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\svchost.exe (Trojan.FakeAlert.H) -> Quarantined and deleted successfully.
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Network\UID (Malware.Trace) -> Quarantined and deleted successfully.
Registry Data Items Infected:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon\Userinit (Hijack.UserInit) -> Bad: (C:\WINDOWS\system32\userinit.exe,C:\WINDOWS\system32\ntos.exe,) Good: (userinit.exe) -> Quarantined and deleted successfully.
Folders Infected:
C:\Documents and Settings\NetworkService\Application Data\wsnpoem (Trojan.Agent) -> Quarantined and deleted successfully.
C:\Documents and Settings\LocalService\Application Data\wsnpoem (Trojan.Agent) -> Quarantined and deleted successfully.
Files Infected:
C:\WINDOWS\system32\drivers\svchost.exe (Trojan.FakeAlert.H) -> Delete on reboot.
C:\Documents and Settings\NetworkService\Application Data\wsnpoem\audio.dll (Trojan.Agent) -> Quarantined and deleted successfully.
C:\Documents and Settings\LocalService\Application Data\wsnpoem\audio.dll (Trojan.Agent) -> Quarantined and deleted successfully.
C:\WINDOWS\system32\~.exe (Trojan.Downloader) -> Quarantined and deleted successfully.
C:\WINDOWS\system32\msvcrtd.exe (Rootkit.Agent) -> Delete on reboot.
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