If you need to create a video of what happens on your computer screen, such as for a demonstration or tutorial, an excellent program to use is Camtasia Studio ($300, 30-day free trial) from TechSmith. TechSmith, as a company, has been around a long time in computer-years. Their focus has always been on utilities for recording, sharing, and using what's displayed on your computer screen. With version 7.0, Camtasia Studio has streamlined editing and added some slick options.
With Camtasia Studio's SmartFocus, you can have automatically created, fully customizable keyframes that will zoom into the area of your screen where your cursor clicks or you input keystrokes.>