Hey! I'm having a similar freeze problem. My laptop is two years old at most, but it has this freeze problem with pretty much all newer distros. When it freezes, no key combination will do anything. I had someone ping my computer at a Linux meetup while I made it freeze, and they said the computer was totally dead when it happened.
The easiest way to make it freeze is to hit the screen brightness keys too fast or to hit them at all during another intensive process. However, it also freezes randomly when it is just "overwhelmed." For example, I could have several windows open (browsing folders, browsing web, and theme settings), click to apply a setting, immediately try to switch to a different window, and it will freeze. This never happened in my older systems.
Systems that freeze:
Ubuntu 12.04 with any operating system - Gnome Shell, Unity, KDE, XFCE, Linux Mint Cinnamon (3.2 kernel)
openSUSE 12.2 Gnome Shell (3.4.6 kernel)
Ubuntu Lucid 10.04 (2.6.32 kernel)
Debian Squeeze (2.6.32 kernel)
Slackware 14 KDE (3.2.29 kernel)*
This one I have installed, but haven't figured out how to get it connected to the wireless yet. Not sure if that has anything to do with it.
I have no idea how to begin researching this. I don't even know if it is a driver issue or a kernel issue.
My thread (unsolved): http://www.linuxquestions.org/questi....php?p=4831934