Suggestion:
Repair the Windows XP Installation - Note: You will forfeit all MS Updates.
Configure your computer to start from the CD-ROM drive. For more information
about how to do this, please refer to your computer's documentation or
contact your computer manufacturer.
Insert your Windows XP compact disc (CD) into your CD-ROM drive or DVD-ROM
drive, and then restart your computer.
(You can also boot with a Windows 98/Me Startup disk with CD support and run
WINNT.EXE in the I386 folder on the CD)
When the "Press any key to boot from CD" message is displayed on your
screen, press a key to start your computer from the Windows XP CD.
When you see the following message displayed on the Welcome to Setup screen,
press ENTER: To setup Windows XP now, press ENTER.
At this point an option to press R to enter the Recovery Console is
displayed. Do not select this option.
On the Windows XP Licensing Agreement screen, press F8 to agree to the
license agreement. Make sure that your current installation of Windows XP is
selected in the box, and then press the R key to repair Windows XP. Follow
the instructions on the screen to complete Setup.
Perform an In-Place Upgrade (Reinstallation) of Windows XP
http://support.microsoft.com/default.aspx?scid=kb;en-us;Q315341
Added info:
How to Perform a Clean Boot in Windows XP
How to Use Clean Boot Troubleshooting for Windows XP
How to Troubleshoot By Using the Msconfig Utility in Windows XP
http://www.kellys-korner-xp.com/xp_conflicts.htm
How to Recover from a Corrupted Registry that Prevents Windows XP from
Starting
http://support.microsoft.com/default.aspx?scid=KB;en-us;q307545
How to Disable a Service that Prevents Windows XP from Booting
http://support.microsoft.com/support/kb/articles/q244/9/05.asp
Use System Files to Create a Boot Disk to Guard Against Being Unable to
Start Win XP
http://www.kellys-korner-xp.com/xp_setup.htm
Computer Stops Responding with a Black Screen When You Start Windows
http://support.microsoft.com/directory/article.asp?ID=KB;EN-US;q314503
Windows XP Stops Responding at the Welcome Screen
http://support.microsoft.com/support/kb/articles/q294/4/27.asp
--
All the Best,
Kelly (MS-MVP)
Troubleshooting Windows XP
http://www.kellys-korner-xp.com
)