Is this an Upgrade from XP. I was wondering how you ended up with the Control Panel link in the My Computer folder?
Has the Start Menu link for the Control Panel previously worked correctly?
Does it work from Safe Mode, or from Normal Mode, but as a different user?
Is there any difference between the Classic View or the Default view for the Control Panel?
How are you accessing "Personalize", from the Control Panel, or a right-click on the blank area of the desktop?
What does Group Policy, or the following Registry locations look like?
Local Computer Policy/ User Configuration/ Administrative Templates/ Control Panel/
Registry Settings
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Policies\Explorer
HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Policies\Explorer
Do you have anything like this mentioned in either of the above?
Value Name: NoControlPanel
Data Type: REG_DWORD (DWORD Value)
Value Data: (0 = disable restriction, 1 = enable restriction)
310560 - How to Troubleshoot By Using the Msconfig Utility in Windows XP
If you have System Restore points then using that may be an option.
You could try the System File Checker program.
How to analyze the log file entries that the Microsoft Windows Resource Checker (SFC.exe) program generates in Windows Vista