Setting up dual monitors in Ubuntu Karmic

I had some time ago set up dual monitors in Windows XP on a Dell Dimension E521 and this worked very well.
So, after getting Karmic (Ubuntu 9.10) installed and working well on the same machine, I wanted to get it displaying on dual monitors, too.
Although, using the nvidia-settings. I could get dual monitor displays, I had some difficulty figuring out how to get Ubuntu to start up in dual monitor display.
In the end, it just came down to correctly modifying the /etc/X11/xorg.conf file.
One thing I found strange was that after setting up dual monitor display in the nVidia X Server Settings dialog, when I tried to save this information to the x configuration file (xorg.conf), I repeatedly got a parsing error.
Anyway, after much research and trial and error, I finally came up with this version of /etc/X11/xorg.conf which works perfectly:

Section "Screen"
Identifier "Default Screen"
DefaultDepth 24
Option "TwinView" "1"
Option "UseEdidFreqs" "True"
Option "metamodes" "DFP-0: 1680x1050, CRT-0: 1280x1024"
Option "UseDisplayDevice" "DFP-0, CRT-0"
Option "ConnectedMonitor" "DFP-0, CRT-0"
Option "HorizSync" "DFP-0: 30-81; CRT-0: 30-81"
Option "VertRefresh" "DFP-0: 56-60; CRT-0: 56-76"
Option "TwinViewOrientation" "DFP-0 LeftOf CRT-0"
SubSection "Display"
Depth 24
EndSubSection
EndSection

Section "Module"
Load "glx"
EndSection

Section "Device"
Identifier "Default Device"
Driver "nvidia"
Option "NoLogo" "True"
Option "TwinView"
EndSection

Note that the monitors I was using were Dell 2007 WFP (1680x1050) and Dell E197FP (1280x1024).
The first was connected via DVI to the computer while the other was hooked up through the vga connection. Nevertheless, the nVidia dialog described this latter as CRT-0.
In any event, this works very well although it certainly would have been better had the two monitors been the same.
However, even 3D effects such as desktop rotation in two screens looks great.
I always use AWN (avant-window-navigator) as a dock in Ubuntu and used this tip to get the dock showing across both screens.
While it works, the fact that the y-dimension on both screens is different (1050 on first and 1024 on second) made it a little difficult. You can see in the screenshots I posted how it looks.
One is actually a screenshot while the other is a photo of the two screens together.