The fast way is to boot up with the installation disk and use the delete option for removing the partition that XP is installed on. Unlike older Fat16, 32 versions you can't simply use a "deltree C:\Windows" or "C:>deltree Windows" command from a dos prompt. With an NTFS boot floppy the manual method to delete files and folders "takes forever". Depending on a few things like going back to ME or deleting XP to use a drive for storage there are other methods as well. One article give different ideas seen here.
"If your computer was purchased with XP preinstalled
If your computer was purchased with XP preinstalled, you should consult your OEM for information on support when changing the OS. This will also apply to any extended service or support contracts purchased with the computer.
If you upgraded
If you upgraded and saved the uninstall files
If you upgraded and saved the uninstall files
and did not change any hard drive partitions, [ i.e. convert to NTFS from fat 32, add hard drive or partition ] you should have the option to uninstall XP from the Control Panel; Add/Remove utility.
How to Uninstall Windows XP and Revert to a Previous Operating System
http://support.microsoft.com/default.aspx?scid=kb;EN-US;q303661
If the option is not available.
How to Manually Start the Uninstall Process to Remove Windows XP
http://support.microsoft.com/?kbid=312569
If the links above do not help, continue to the following steps
ONLY after backing up all important data and anything that cannot be restored from other media. All data will be lost after proceeding with the following instructions.
Identify the file system
- Identify the file system that you are using. To do this, follow these steps:
- Double-click My Computer on the desktop or Explorer.
- Right-click the disk that you want and then click Properties.
- Look for the File System entry.
- If the disk is formatted in NTFS, your options for returning to Windows 95, Windows 98 or Windows Me are limited. Those operating systems do not read or recognize NTFS and you cannot convert the disk to use the FAT or FAT32 file system. The bootable disk that you use and the drive on which you want to install Windows 95, Windows 98 or Windows Me cannot use NTFS. Microsoft does not support any third-party solutions for converting NTFS to FAT or FAT32.
- If the drive is using the FAT file system, you can install any operating system. If the drive is using the FAT32 file system, you can install Windows 95 OEM Service Release 2 (OSR2) or later.
The above was copied from:
http://support.microsoft.com/default.aspx?scid=kb;EN-US;q31405