Hello sweta,
i am really thankful to you for your suggestion . i was trying to install windows xp in pre-installed vista laptop but i was getting failed. but searching in google and getting your procedure to do so really helped me a lot and i could do it. thanks again . plz do continue your such useful suggestions. my e-mail id is ruturajm704@gmail.com. if you have more tips like it , then plz send it to my e-mail id.
thanks a lot.