Are they both xp ?
When you restart your system, and you get a choice of two operating systems, you should choose the one you want to keep installed on your machine.
Once the startup process is done, and your computer is ready to accept tasks to perform certain functions, you click on the "My Computer" icon and locate the hard disks, removable storage devices, and more.
In the hard disk box you should see two drive icons, like "C", "D". If the copy you installed later need to be cancelled, it must reside on the "D" part of the hard disk.
This is because the "C" is where you initial copy of the Windows Xp resides, and it is the one you want to keep installed as the only copy on your computer.
The way you should get rid of the "D" copy is to format the "D" part of the hard disk. just right click it, and choose format. This will delete the Windows Xp copy you don't need.
