Q: How to disable all interactive editing control for GRUB menu?

1. Read General Notes

2. grub
   
   grub> md5crypt
   Password: ****** (ubuntu)
   Encrypted: $1$ZWnke0$1fzDBVjUcT1Mpdd4u/T961 (encrypted password)
   grub> quit
   
   sudo cp /boot/grub/menu.lst /boot/grub/menu.lst_backup
   sudo gedit /boot/grub/menu.lst

3. Find this section

   ...
   ## password ['--md5'] passwd
   # If used in the first section of a menu file, disable all interactive editing
   # control (menu entry editor and command-line)  and entries protected by the
   # command 'lock'
   # e.g. password topsecret
   #      password --md5 $1$gLhU0/$aW78kHK1QfV3P2b2znUoe/
   # password topsecret
   ...

4. Add the following line below it

   password --md5 $1$ZWnke0$1fzDBVjUcT1Mpdd4u/T961 (encrypted password above)

5. Find this section

   ...
   title		Ubuntu, kernel 2.6.10-5-386 (recovery mode)
   root		(hd0,1)
   kernel		/boot/vmlinuz-2.6.10-5-386 root=/dev/hda2 ro single
   initrd		/boot/initrd.img-2.6.10-5-386
   savedefault
   boot
   ...

6. Replace with the following lines

   #title		Ubuntu, kernel 2.6.10-5-386 (recovery mode)
   #root		(hd0,1)
   #kernel		/boot/vmlinuz-2.6.10-5-386 root=/dev/hda2 ro single
   #initrd		/boot/initrd.img-2.6.10-5-386
   #savedefault
   #boot

7. Save the edited file (sample)