If you want to control your mouse pointer with the keyboard, Windows XP and Windows 7 provide a way:
Left Shift +
Num Lock keys all at once and a prompt will appear telling you that you have activated mousekeys, select ok then you can control the mouse with the numpad.
The controls are:
9: move the mouse
5: mouse button click
+: double click
Insert: hold down mouse button
Delete: release mouse button (after holding it down with insert)
-: select which mouse button the above controls will click (left, both or right respectively)
Num Lock: disable mousekeys.