There are a lot of options when talking about PowerPoint to video converters.
I was looking recently for one such solution and i stubled on a quite detailed comparison chart.
It's comparing 5 such PPT to Video solutions: Cucusoft DVD Ripper + Video Converter Ultimate Suite, Aimersoft DVD Studio Pack, Avex DVD & Video Converter Pack, AVS Video Converter and Aimersoft DVD Converter Suite.
The comparison in broken down in a lot of categories like: Input Formats Supported, Output Formats Supported, Key Features, Support.
Check it out: http://www.topsreviews.com/reviews/dvd-video-converter-suite-review.html
All the converters have free trial periods so it would be best to try each of them and see what you like.
Hope it helps