I'm really demoralized. I have a desktop PC that ran great with 10.10; I finally decided to put 12.10 on it. I've done countless ubuntu installs and the only big problem I ever had is that on one of my laptops, you get a huge screen with part of the wallpaper that you can't do anything with (since I can't use the system, I forgot if it was 12.04 or 12.10).
But this desktop install of 12.10 was the WORST ubuntu install I ever did. Dash is impossible to use, whenever I click on it, graphics go berserk and I have to force restart (by hardware button).
I tried to change driver from the top right panel system settings to propriety (it has a NVidia GEForce something), and there's no clear indication whether I succeed, and no change in the situation. I try to install gnome-session-fallback but it just hangs at "0% Headers" thing.
It's a completely unusable system. I am utterly disappointed at how worse things have become since the awesome Gnome 2.X. I had recently posted a rant on ubuntu saying that I love it but feel that something is lacking graphically. Now, my nightmare has become true. Not only is something not lacking in terms of prettiness graphically, but there is no properly functioning graphics anymore.
My last resort is this forum. After the failed attempts to have a usable install of ubuntu 12.X on the laptop and the desktop; if there is no solution you know of, I guess I have to either switch to another linux distro or win 7 (which I dual boot with anyway).
I can't get over my shock, I was so in love with ubuntu for such a long time.