Formating the Pc

1.go to bios setup by pressing DEL or F1 on the post screen
2.change first boot priroty to cdrom.and save changes
3. then put your windows xp cd in the drive
4.the message show as ''press any key to boot from cd" press any key
5.now the setup starts,after some time the message shows as "press enter to install windows xp" then press F8 to accept the licience.
6.with in a minute it shows your curent os drive. that time press "esc"
7then you will find the format option