#1 Why are you removing XP Pro ?
#2 What will you replace it with ?
#3 Look for [b][u]**[/b][/u] below.
If as I suspect you are removing it to start again on a 'clean slate' you have to know that you will lose ALL trace of your emails, letters, pictures, music files, everything - all your data when you re-install. You would be well advised to SAVE all the data that you wish to keep, prior to performing a fresh install.
Now to your question ~ You cannot 'uninstall' XP Pro - what happens is, the installer for XP Pro will format the hard drive prior to installation, thereby deleting whatever previously existed on that particular hard drive. That's how it works.
[i]Logically you cannot delete an operating system while the computer is using it![/i]
To perform a 're-install' you have to place your XP Pro disc in the optical drive and turn your computer on. It will then BOOT from the CD/DVD drive and begin the installation of XP Pro. Initially the installation will format the hard drive (removing any access to existing data files) then install XP Pro over the top of the freshly vacated space.
Typically, a newly installed XP Pro on a 30GB hard drive, should leave you with about 25GB of free space.
[b][u]**[/b][/u] Depending on what your computer is (which Make which Model) you may not actually have an XP Pro installation disc - what you might have is a Recovery Partition on your hard drive. If you do, you need to boot the computer and immediately press a key combination (usually [b]Alt+F10[/b]) to invoke the hidden installer - this will return your computer to factory settings, just like it was when you first received it.
[b]Be aware - anything that you may care to retain, any data at all, should be saved first before you re-install.[/b] :)