vim /boot/grub/grub.conf

method1:

               timeout=5-------->timeout=0      //// no grub view when starting the system.(my new idea)

method2:

              add a line:

              password=*******                     //// the password of your GRUB!

method3:

              encrypt your password:

shell> grub-md5-crypt

Password:

Retype password:

$1$XTpcp0$Nzyu8KcG4HHCnYLdHLPCs/                       ///It's secure! It was generated dynamicly!You do it again, the code is going to be different!

shell>vim grub.conf

password --md5 $1$XTpcp.....       /// the md5 code!