Up until 2 days ago Ubuntu 12.04 was going simply great, then the update manager prompted for some updates and I continued as usual.
After that I continued to use the computer for few more hours then I restarted it but seems dead. I unplugged the power cable, waited about 30 sec and restarted, and it does work, however with my great surprise once it reaches the Grub screen and I select the OS I want (I have only Ubuntu 12.04 on this system) the computer shuts down and I am unable to restart it. I have to unplug the power cable and wait a few seconds until I can restart it.
If I choose the second option, it does not shutdown; but after a zillion of lines it takes me to a new window where I can chose what option i want. I tried to check the file system and it was ok; if i click "repair broken package" and I agree to upgrade i get numerous lines says "error unable to fetch....". If I chose low graphic mode I am taken to a second window but whatever is the option that I chose I get a blank screen which stays there for several minutes, with a dash blinking on the top left corner of the monitor but nothing happens.
I am currently working with a live CD but and I wonder what would be the best way to proceed. Can I fix it from the live cd? how?