Question 1: Why am I getting a text login when I asked for a GUI?
Question 2: Why does the display only get output for a few seconds at a time?
Question 3: What is stressing my hard drives?
You are getting the GUI, kinda. It sounds like its trying to load gdm/xdm/kdm but XFree86 isnt working with the display driver selected, so its booting back to text. Then trying to open again, and failing over and over.
first thing you gotta do, boot into a mode that you login to.
boot into init 3, or single
then use chkconfig to stop xdm/gdm from starting, until you get XFree86 working.
OR fix Xfree86, and leave it running.
Ul have to do some research on how to get your display working for your model of video card/laptop. Perhaps start another post with that in it.