In Ubuntu 11.10 (and maybe earlier) they thought it would be cute to change the background of the GRUB2 boot screen to purple, making it match the rest of the Ubuntu color scheme. I hate the background color though. It looks especially bad on my laptop where it looks like the screen backlight had gone bad. So after some Googling around I figured out how to change it. As
root you will need to edit
$ sudo vim /lib/plymouth/themes/default.grub
The file is only three lines long and looks like this:
if background_color 44,0,30; then clear fi
Change the first line to read:
if background_color 0,0,0; then
That’s it! Enjoy.