How to convert a PowerPoint presentation to a video file

"Download Office 2010 (free), open your document, and navigate to File > Share > Create a video. You can export your presentation as a .wmv file.

From my experiences, third party solutions are expensive, if not free and watermarked, and the quality is mediocre. Who wants to pay for something they use infrequently, well, for me at least."

I don't think that there's a direct way...but you could always go around and record your screen while playing the presentation.