I did the most recent updates as I regularly do but this time I got the black screen of death after restarting. No way I can get the system to boot even though the boot options and BIOS settings look right to me. I ran Ubuntu 12.04 from a cd and I can see the HD partitions but can't access the files because I am not the owner(owner: 1000 - user #1000). What is the best way to recover my data? What boot recovery tools are safer/easier to use? I wonder if this happens to other distros that have a reputation for more testing like Fedora or OpenSuse. Any comments would be welcome on this subject. Thanks, Pablo
One thing you can try right off the bat is to boot up your computer while holding the left SHIFT key until you get to the GRUB prompt. Then select an older Kernel version to boot using the arrow keys and enter key. You may have to choose "Advanced Options" to get to the kernel versions.
Failing that, you can try booting with Recovery Mode, also from that same Grub menu. For backing up, this answer should help you access the files on your hard drive while booted with the Live CD. How do I get root access to hard drive from livecd?
If you still cannot access your hard-drive files, they may be encrypted. Try this answer to access encrypted drives & files: How to recover encrypted home data with Live CD?