Wait, Aero crashing points to a video driver problem.
You should probably reboot in safe mode (F8 during bootup, select "Safe Mode with Networking"), go to the website of your video card or computer manufacturer and download and install the latest video driver for Win Vista/7.
Originally Posted by palmtree5
Actually, if you want exactly 80 GB, enter 81920
*Sigh* I was never THAT good at math.......