if USB is your main concern you could you the XP CD to renstall the USB drivers.
However I suggest you boot from the CD, and repair the installation.
This will require you to re install all XP updates, the easy part is downloading XP sp3, save it to your hard drive, before you the repair, then run the install of XP sp3. After you do this there will be minimal downloads before your up to date.
How to perform an in-place upgrade (reinstallation) of Windows XP
http://support.microsoft.com/kb/315341
Use method two; skip the repair using Recovery Console, and select a new install, XP will detect the previous install and offer the chance to repair it, all you data and application will remain inplace. However, I suggest you back up important data.
Method 2: Repair install of Windows XP by starting your computer from the Windows XP CD
To reinstall Windows XP by starting your computer from the Windows XP CD, follow these steps: 1. Insert the Windows XP CD into your computer's CD drive or DVD drive, and then restart your computer.
2. When the "Press any key to boot from CD" message appears on the screen, press a key to start your computer from the Windows XP CD.
Note Your computer must be configured to start from the CD drive or DVD drive. For more information about how to configure your computer to start from the CD drive or DVD drive, see your computer's documentation or contact your computer manufacturer.
3. You receive the following message on the Welcome to Setup screen that appears:
This portion of the Setup program prepares Microsoft Windows XP to run on your computer:
To setup Windows XP now, press ENTER.
To repair a Windows XP installation by using Recovery Console, press R.
To quit Setup without installing Windows XP, press F3.
4. Press ENTER to set up Windows XP.
5. On the Windows XP Licensing Agreement screen, press F8 to agree to the license agreement.
6. Make sure that your current installation of Windows XP is selected in the box, and then press R to repair Windows XP.
Note If Windows XP was preinstalled on your computer, and you do not have the Repair option, contact your computer manufacturer to make sure that you have the installation CD for a repair install.
7. Follow the instructions that appear on the screen to reinstall Windows XP. After you repair Windows XP, you may have to reactivate your copy of Windows XP.
For more information, click the following article number to view the article in the Microsoft Knowledge Base:
310064 (http://support.microsoft.com/kb/310064/) How to troubleshoot Windows XP Setup problems when you upgrade from Windows 98 or Windows Millennium Edition
Any queries please post back,
Jeff
