heres Installshields Expo Walkthrough.

Basically - its a Demo/walkthrough piece of kit.  Record the screen/application (with full control over how much screen real estate you record), then go through frame by frame and configure mouse movements and 'speech bubbles' etc etc

A professional piece of kit thats easy to use.

Perfect for 'How-To's' and well...walkthroughs...the clues in the name i guess!

Enjoy!