How to remove an item from GRUB boot menu 2nd Way.

There is another way to remove items from GRUB menu. By deleting the files in /boot. To remove the item in the GRUB do as shown below.

Open Terminal (ALT + CTRL + T)

Enter the Command.

gedit /boot/grub/grub.cfg

Now search for ### BEGIN /etc/grub.d/10_linux ###.
After that line you will see the items of your GRUB menu.

Select which is the item you want to remove. Suppose we want to remove Ubuntu, with Linux 2.6.32-30-generic. For that find the line. and in between {…..} the characters find initrd and memorize the location after the text initrd.

Go to the location. For that do as below.

Open Terminal (ALT + CTRL + T)

Enter the command.

sudo nautilus

A root file browser window will display.
Go to /boot folder and find the file with the name after initrd text you found above.
Delete the file. But be careful. If you delete the wrong file then you are in danger.
So be Careful.