Format your computer via your hdd

The limitation is that u should have a OS previously installed and u can't format c drive except from it u can format all other drives

1. Make a image of your xp sp2 in your hdd and mount this image via demon tool,alchohal, clone cd or any other virtual drive
2. Now double click it 
3. A windows appears and ask u what do u want to do
4. Select install windows xp professional/home edition 
5. A new windows open in that
6. Click next and it will ask for key
7. Give the key
8. Click next 
9. An option comes copy files in here
10. Click copy files in hard disk 
11. Press next
12. It will start copying files in your hdd and restart the windows 
13. Follow the normal procedure and u can format any of your drive.