Changing / Breaking root password in Linux even when grub is password protected

Boot from CD
It will take you
boot:
type 'linux rescue' at this command prompt and enter

It will take you to some interface with some questions , answer them properly .
The system will go to temporary command prompt.Then issue the following commands

[bash$] chroot /mnt/sysimage [Enter]
[bash$] cd /boot/grub [Enter]
[bash$] vi menu.lst [Enter]

now in this file you can see a line beginning with the word 'password' remove this line and save the file.

[bash$]exit
[bash$]exit

Remove the CD.

Now system will be rebooted and you can see the grub without a password.