I am not sure if I completely understand your problem, but I had a similar problem earlier this year when xorg was upgraded.
Press F3 at the boot screen then return
add a 3 to the end of the boot line - press return again.
login as root (su) at the console
then type startx and it should take you to the desktop.
I downloaded the 6/27/11 version of PCLinuxOS KDE. Md5sum check OK. Burned it to a LiveCD. When I boot it, the choices are F1 Help, F2 Language, F3 800x600, F4 CDRom, F5 Driver, F6 Kernal Options.
Pressing F3, I get the following choices: Text, 640x480, 800x600, 1024x768. I believe the older versions of PCLinuxOS had an F3 Boot Options, but this one does not.
If I press F6 Kernal Options, then press "default", it brings up a line where you can put in Boot Options_________ . I tried typing 3 and pressing Enter, but that starts to load the CD which partially loads, but then hangs on "Starting UDEV"
I also tried to boot into CONSOLE. But in the middle of loading, it hangs with a corrupted screen and the computer is locked up.