"Screen goes crazy" usually means unstable hardware. Looks like a pretty generic BSOD so I'd be checking temps and returning to stock clocks on CPU and GPU.
If it is Vista, then you can get some more information about your error by poking around the "Event Viewer" and "Reliability and Performance Monitor". Typing those names into the start menu and pressing enter should launch them.
As for the access denied, have you tried right-clicking on the Notepad and clicking "run as administrator"? I'm assuming Vista from OS version 6.
EDIT: The first file in your list is a memory dump file; notepad won't be able to get anything useful from it (unless your brain can easily convert garbled ASCII)
A quick search turns up this article and forum post about memory dumps:
Locating Memory Dump Files - Vista Forums How to read the small memory dump files that Windows creates for debugging