I thought it would be quick, anyway.
I've done this in the past using Snagit which has a video capture function. But for whatever reason the act of recording the screen caused my actions to suffer a terrible delay. For example, click a menu item and wait 45 seconds for the menu to react. Not good. I lost about an hour trying to get the system to work correctly while recording without success.
Over lunch a coworker suggested using a free tool called CamStudio. I installed it, changed a couple of settings to record audio and boom! Done. Free and easy. Two of my favorite four letter words.