You got Ubuntu 7.10. I can tell from your description of what happened. IMHO, it's the worst release Ubuntu has ever done. They focused so hard on eye candy, they screwed the rest of it up. First, fix part of it: Go to system on the menu bar, I can't remember if it's under administration or preferences, but you need to find the desktop effects and turn them off. I believe the setting you will be looking for is "none". Then you need to go to Ubuntu's forum and search for turning off desktop search. These 2 things should make 7.10 much more useable.
Next, force closing windows: hit alt F2, and type in
killall application name
...orrrrrrr go to system, administration, system manager and highlight the stalling app, then click end process, answer the popup (don't click wait). Rebooting without shutting down is just as damaging in a linux environment as any other os, it's not very friendly with your hardware either...particularly hard disks spinning down without being dismounted. As you go, you will find the need to force reboot is much more rare in Linux as you get to know it better.
My recommendation: Go back to Ubuntu, download fiesty fawn or dapper drake, format your hd and reinstall either of those. I made the mistake of upgrading to Gutsy Gibbon on one of my machines and I have had nothing but a media nightmare since, and this is a fairly powerful machine. However, there are some who have had great experiences with it...just not me. If you wan the newest version, I personally suggest you wait until they release the next LTS (long term support) version or go to Debian all together.
Edited by Joedude, 22 December 2007 - 10:56 AM.