Changing vista to XP for HPPavillion2700

Hello,

I have buy HP pavillion DV 2700 (2750 ee)

it is in Vista base , i want to install winodws XP to this ,
how can i change this , anybody can help me in this regard.

or if you know any service center those who will solve this problem..than please give me the contact adress and tel no:

my email id : annu06_dubai@yahoomail.co.in

i want only banglore service center ....bcoz i am staying in banglaore