Remove GRUB loader

Sometime we need to have 2 operating systems, e.g. ubuntu+windows xp.
Install XP first, then install Linux. But maybe later on, we want to delete the linux and its partition. After we delete, we cannot access the windows XP! GRUB loader error? What should we do?

Don't worry, you can have your XP back as long as you don't delete the partition. Grab your windows XP cd, and boot from your windows XP cd, same as if you want to install XP. Then wait until it asks for options. Choose Recovery Console by pressing 'R'. Then the screen will becomes black, then wait. Choose the windows you'd like to recover. Usually the first one, then input the number '1'.
You will now on command prompt: "C:\WINDOWS"
do these commands below:
- cd ..
- fixboot c:
- fixmbr
- bootcfg /rebuild

After that type exit, enter then your PC will be rebooted. If it's working properly, usually you will boot to your XP again. Good luck!