It seems like it's very difficult on this computer to get the mouse right at the corner of a window so that I can resize it. My other box seems much less sensitive. Is there a way to change that setting?
The problem is the border size of the windows. The default theme in Ubuntu has a very narrow border. You can change the windows border theme in "System, Preferences, Appearance". However, I haven't found a theme I like better than the default, so I've taken to using a shortcut I saw posted somewhere else. You can also resize a window by holding down the Alt key and using your middle mouse button. There's some dead space in the middle of the window using this method. Just be near the edge you want to resize, and it will work. Then you don't have to grab the single pixel of the border. ;-)