windows 7 and ubuntu dual boot : windows 7 boots in background but showing distorted screen of ubuntu

If you have installed Windows 7 and Ubuntu as a dual boot and when you boot windows 7, it loads a distorted screen of Ubuntu although you can hear the windows 7 start up sound but you are not able to do anything because nothing is displayed.

Here is the solution.

sudo nano /etc/default/grub
Now Uncomment following line.
GRUB_TERMINAL="console"

Update the grub.
sudo update-grub

Restart your system.
sudo reboot