You machine appears to most likely have the ATI Radeon 4250 graphics adapter based on specifications found elsewhere. You can confirm this by running
sudo lshw -C display
If you are currently using the Radeon driver, try using the fglrx driver and vice versa. Radeon support is pretty scratchy at the moment. Your bug report will not go anywhere because it has been filed against xorg when it should have been filed against fglrx or the radeon driver after further testing. Have a look at this previous question on installing the fglrx driver.
A black screen does not actually mean that the machine is hung. If you can press CtrlAltF1 and get to a text console to install drivers and reboot safely etc, the machine is not hung. This is an important distinction to make at this point.