I've had this problem from day one. After my system boots up and I have clicked on an icon or two to run, the system quits responding. No error messages or anything. The mouse and keyboard just will not respond normally. If I hit the CTRL-ALT-DEL and select anywhere in the window that pops up, the system unlocks and is fine for the rest of the session. Now I do not actually do anything in the CTRL-ALT-DEL window. I just click, usually on the blue header bar somewhere, and the mouse/keyboard begins responding again. Then I just shut down the window and continue on without any further problems. I would think it has something to do with startup but for the life of me I can't figure out what is causing the hang.