I get the grayed out screens. What is happening on my system is the
same thing as a grayed out menu, i.e. something is not available, in
my case my router fails me and my connection is lost. Because Ubuntu
is waiting on hardware issues or more correctly my router transmitting
information it grays the window effected.

As for USB problems if not a consistent problem it to is unlikely a
problem with the OS is the USB system suported by Linux? I am thinking
some functions needed for the hardware may not be. Maybe a look for
updates may be in order.

I have been using the 64 bit OS 8.10 from the time it came out. I am
happy with it. I just installed studio for the movie editing using 64
bit and 8.04, like before with 8.04 will not work for the Internet
connection but I don't care I will boot into the system I need.

Hope some of this info will help you trouble shoot your system.