Well I don't know what I did right, but I now have 1680x1050. The last thing I did was switch over to laptop only (disabling the 22"). Then switching back to the 22" and disabling the laptop. /etc/X11/xorg.conf is not there. Only the xorg.conf_backup that I made.

This is the output of xrandr:
Screen 0: minimum 320 x 200, current 1680 x 1050, maximum 1680 x 1200
VGA-0 connected 1680x1050+0+0 (normal left inverted right x axis y axis) 473mm x 296mm
   1680x1050      60.0*+
   1280x1024      75.0     60.0 
   1152x864       75.0 
   1024x768       75.0     60.0 
   800x600        75.0     60.3 
   640x480        75.0     59.9 
   720x400        70.1 
LVDS connected (normal left inverted right x axis y axis)
   1024x768       60.0 +   60.0 
   800x600        60.3     59.9 
   640x480        59.9     59.4 
S-video disconnected (normal left inverted right x axis y axis)

Love to know what fixed it. The only thing I can think of is that by removing xorg.conf and then going back and setting up the 22" monitor again it used the correct resolution for that monitor rather than reading it from xorg.conf (because it wasn't there).