Sorry, this got sent before I was done. There is a red power button in the
lower right corner, and when I click on it, a chrome://googletube window appears
and the Ubuntu menu items return (until I close the googletube window, then they
go away again).

I haven't yet looked at Firefox extensions, but I will do so.

Any chance you have a Dell computer there with Intel graphics on the
motherboard? I ask because when I powered up the Ubuntu 10.10 the power off
and most of the right-side buttons were gone.

I tried to re-do the monitor size with the monitor settings button, but it
didn't work. No more Dells here, I re-did Windows on it and gave it to a needy
father for his kids' belated Christmas.

I had the same problem after I applied an update to my 10.10 this week.

Using HP G60 Laptop.

I've loaded SeaMonkey, and it appears to work, but I can't find any option to
make it the default browser in the Preferences section.

I've had too many problem with FireFox, both in Wondows and Ubuntu, so I think
I'm going to drop it.

Different to my experience of upgrading because before I had only three
setting available to set the resolution of the desktop but after getting
10.10 I get a full list from 640x480 to 1360x768 so you need to get
drivers for your motherboard/graphics card from the manufactures for Linux.

It is a homebrew quad-core Athalon with ATI graphics.

You will need to get Drivers for your Motherboard and graphic card that
work in Linux.

Before you go compiling a new kernel mod for the ATi video card. You may thank
about making a backup you bookmarks from firefox.

Try to sudo apt-get -f install "firefox"
else
sudo apt-get purg "firefox"
rm -rf ~/.mozilla
sudo apt-get install "firefox"

This may or may not help :|

You can change default apps and other stuff thou control center in gnome. just
run "gnome-control-center" from the console.

but the system had been working just fine for over a
year. I guess I could try to figure out which update did it in, but it was
easier to just remove FireFox and switch to SeaMonkey.