Take a look at this post over at Ubuntu forums for a very comprehensive, yet easy to understand guide to Grub2. Noteworthy mentions are as follows:
“At first boot, there will not be much difference in what the user sees on the boot menu. The one exception is a clean install of Ubuntu 9.10 with no other installed operating system. In this case, GRUB 2 will boot directly to the login prompt or Desktop without displaying a menu. Other major differences:
- No ”/boot/grub/menu.lst”. It has been replaced by ”/boot/grub/grub.cfg”.
- Hold down SHIFT to display the hidden menu during boot (formerly ESC is GRUB legacy).
- There is no “find /boot/grub/stage1” at the grub prompt. Stage 1.5 has also been eliminated.
- The main menu file, ”/boot/grub/grub.cfg” is not meant to be edited, even by ‘root’.
- ”grub.cfg” is overwritten anytime there is a update, a kernel is added/removed or the user runs `update-grub` *
- The user can use a custom file, ”/etc/grub.d/40_custom”, in which the user can place his own entries. This file will ”not” be overwritten.
- The primary configuration file for changing menu display settings is ”/etc/default/grub”.
- There are multiple files for configuring the the menu – ”/etc/default/grub” mentioned above, and all the files in ”/etc/grub.d/” folder.
- Other operating systems, such as Windows, should automatically be recognized and added to the menu.
- No changes made in the configuration files will take effect until the `update-grub` command is also run.”
Big thanks to our author : http://ubuntuforums.org/member.php?u=223945
Original Post : http://ubuntuforums.org/showthread.php?t=1195275