A good way to try out Ubuntu is by installing it alongside Windows, which is often known as dual-booting. If you are dual-booting Windows with Ubuntu, then Ubuntu will make itself the default operating system when booting-up. You get a few seconds to switch between different operating systems with the arrow keys.
But, have you ever wanted to change the boot order? You can change the default operating system from Ubuntu to Windows by editing the Grub boot menu. Let’s take a closer look at how this can be done.
How to Change Boot-order in Ubuntu
Before proceeding forward, notice the current boot order as it appears on your computer. This step is important because you will need to edit the boot order in a file. Numbering for Grub starts at 0 instead of 1, therefore the first boot entry will be the 0th entry, the second boot entry will be the 1st, the third boot entry will be the 2nd, and so on.
Press Alt+F2 (or you can also open up a terminal) and enter the following command:
You will get a prompt that will ask you for password. Enter your password and click on OK.
The above command will open a file. Find the GRUB_DEFAULT=0 entry. This means that the first boot entry (which will be Ubuntu) is the default option to boot your computer into.
If you want to change this order and make Windows the default entry, then change “0” to its corresponding number. For example, if you are dual-booting with Windows, then in most cases, you will need to change it to GRUB_DEFAULT=4.
Save the file and exit out of the editor.
This is the last step. Open a Terminal and fire up the below command:
Ubuntu will ask for your password and then processes your command.
That’s it. Next time you boot, you should see that Windows will be the default operating system. This method is tested and works on Ubuntu 12.10 but it should work on older version of Ubuntu also.