I was using Ubuntu 12.04 LTS smoothly and started forgetting MS-Windows. But recently I notice a upgrade notification of Ubuntu 12.10 in update Manager. I started upgrading. It took lot of time and after that machine re-booted and I got only a blue screen. I tried a lot to solve this problem but all of my effort was useless.
I uninstalled Ubuntu from windows Vista and then installed my original 12.04 again. Now, I just updated ubuntu instead of upgrade and then noticed my desktop icon are missing, right click not working on desktop and Libreoffice menus are not fully visible.