Install xp from usb on preloaded vista

I have been searched all over the internet from the past 20 days and founded many solutions for installing xp from usb but I had choosed only multiboot cmd and this did worked for my lenovo laptop since the dvd was dead and it was already repaired several times so i dont have any hopes on it if repaired also.I describe below steps to format hard drive and install xp
First download USB_MultiBoot from boot land forum or msfn.org and extract to a new folder without spaces.
2.Turn off UAC.I mean user account disable that is adminitrator
For this you need to click start and then run
In the box type msconfig and when popup box opens click system configuration and then click Tools tab.Scroll down and look for disable uac protection.highlight this option and click ok
msconfig-uac
Now you have disabled user account off.
Go the folder where you extracted files and open it.From that folder right click on usb_multiboot.cmd and run as administrator.once the command prompt started and follow the steps with screen shots
911cd.net/forums//index.php?showtopic=20089&st=11
Once you followed the steps and if their is any problem then look the boot.ini
I got the boot.ini problem because it always tried to boot from the other drive but i changed the values of rdisk and partitions and it worked.
And for the lenovo y410 xp driverds their are some roubles afterinstallation since the mouse pad dont scrolland their are even few more issues with this.So please think before and delete your partitions etc.
My suggestion is never delete the hidden partition this can help at any time to recover vista or else you need to pay the money