GRUB Customizer is the software that can be use to customize our own version of Linux distribution.Small software that have some setting that we need. You can get it on Ubuntu Software Center. Here some image and setting that we can change through it.
1. List configuration of distribution that we have.
2. General Setting. Boot timeout etc..
3. Appearance Setting. Here is the setting to change GRUB boot image, resolution and others. Beware of the resolution depend on your graphic card specification.
4. Advance Setting shows some shortcut setting.