Here's what is happening:
White screen- compiz is enabled, but there is no 3d acceleration (I've had that experience before).
When you took out fglrx at interactive startup, all that happened was you did not load the kernel module. The kernel module enables things like 3d acceleration.
To get a fix (one method)- press ctrl-alt-f5 to get to a console. Log in as root and then edit /etc/X11/xorg.conf. Look for Section "Device" and change the driver to "fglrx". As an example from my own xorg.conf:
BoardName "Framebuffer Graphics"
Don't worry about the Board Name. This can be anything. Save the file and then reboot.
If you need help editing from a console, write back.
If everything comes back after a reboot, take a look at this thread for further information: