Something I learned that Windows 7 has (you'll have to check your own versions because it may or may not exist in other versions.) Mouse Keys.
control panel -> Ease of Access Center -> Make the mouse easier to use.
This will allow you to use the number pad (num lock must be on) buttons of 5 and + as a mouse click.
You will need to select the "Turn On mouse Keys" box. Now I'd select the "Set up Mouse Keys" feature.
From there it should be self explanatory.
Also on this same page is "make it easier to manage windows"
There is an option for "Activate a window by hovering over it with the mouse"
Meaning that whatever your mouse is over, that window has focus and won't lose the focus. This could be handy for some people.