This is one of the lessons i learned on my own by screwing up the display configuration of my GUI of Ubuntu (Linux). So what happened is that i changed the refresh rate and resolution to match my TV (It's a HDTV which supports VGA) and everything was messed up, here is what i did
I suggest you backup your display settings before making any changes otherwise you will be sitting like an idiot like me :P
1. Either boot in recovery mode OR you can simply press CTRL+F1 to go in the CLI (Command Line Interface)
2. go to /etc/X11
[code]cd /etc/X11[/code]
3. Baclup your config file
[code]sudo cp xorg.conf xorg.conf.backup[/code]
4. Fortunately for me ubuntu had already kept my last configuration file so all i had to do was to over write the current one
[code]sudo cp xorg.conf.1 xorg.conf[/code]
5. Than had to reboot the machine [code]sudo reboot[/code]
there were couple of backup configurations in the folder so it was trial and error procedure till i found the configuration which was working for me
this was a hap hazard way of describing things but what the heck, hopefully it will help someone out or perhaps me in the future to recall my footsteps to solve the problem :P