I have Linux mint 16 and trying to change the boot order in grub.
 

When i execute 'sudo nano upgrade-grub' nothing happens after i have edited the default grub list as instucted

Try 'sudo update-grub'

Better yet, try: sudo update-grub. nano is a text editor and your command is telling the system to open with root permissions a file named: upgrade-grub.

did as you say get a message containing 'line 1: ^G#: command not found' explain?

Post the actual command and output as you entered it and the output. If you actually entered it correctly and got a command not found you have serious problems. Of course, Mint 16 is outdated and unsupported for over a year so it's time to upgrade or reinstall anyhow.

Check line 1 of the default grub file and remove ^G if it is there.

I have deleted ^g: and now I get 'sudo update-grub
Searching for GRUB installation directory ... found: /boot/grub
/etc/default/grub: line 1: If: command not found' when I run 'sudo update-grub'

you didn't happen to delete the # that is suppose to be at the beginning of the line?

open terminal and issue:
and your feedback should be
Does it look like a missing "#" on line 1 of /etc/default/grub ?

If it is missing, you'll have to add it. Be careful. Ask if you are not sure.