Grub Menu

Grub is the bootloader for Linux.

Version
Grub2 is the current installment of the Grub software. However, the long version number for Grub2 is either Grub 1.97 or Grub 1.98. Don't be fooled; this is still Grub2.

Show Boot Menu in Ubuntu
Ubuntu suffer from the "software which likes to act smart"-syndrome.

By default, Grub does not show a boot menu. Despite that the manual claims otherwise, a dual boot system with Linux, FreeBSD and OpenSolaris will not show a menu.

The trick to have the menu shown again is to set (or actually unset!) the GRUB_HIDDEN_TIMEOUT parameter in /etc/defaults/grub.

From the Ubuntu Grub2 manual:
 * GRUB_HIDDEN_TIMEOUT=0:Boot the default option immediately, do not wait or show a menu.
 * GRUB_HIDDEN_TIMEOUT=5:Wait 5 seconds, but do not show a menu
 * GRUB_HIDDEN_TIMEOUT=:(no value set!) Show a menu

The GRUB_TIMEOUT then determines how long the menu is shown.

So in order to show a menu for 5 seconds, use these options:

GRUB_HIDDEN_TIMEOUT= GRUB_TIMEOUT=5