things you might want to do with your grub:

1. remove/change the boot countdown
2. change the background theme
3. change the text color theme
4. change the default operating system
5. password protect your bootloader

you can do all of this with SUM, or startupmanager, found here.

you might also want to change your usplash screen, and show the loading dialog. the first one can also be done in SUM, for the latter, you need to manually edit your menu.lst file, so..

sudo gedit /boot/grub/menu.lst

remember to backup.
then look for a line that looks like this..

kernel /boot/vmlinuz-2.6.20-16-generic root=UUID=ef286b15-9709-4448-92a6-ce70fe73a54b ro quiet splash vga=794

remove the quiet keyword, save it, then you’re done.

some notes: the format accepted for themes is only .xpm.gz. a good resource is gnome-look.org.