Setting up a UK keyboard layout
Solution 1:
On ubuntu fresh install:
Login and press Ctrl-Alt-T to open a Terminal and run:
setxkbmap -layout gb
To get UK keyboard with double-quotes on Shift-2 and @ sign on RHS.
Solution 2:
Go to Keyboard layouts under system settings, and click on it. Once open remove English (US), and add the English (UK) that you want. Click on the Plus (+) sign to add, and the minus(-) sign to remove. See images below.
(It will be English UK with Extended Win Keys)