Free solution:
- Keynote can record a running presentation with the mic-audio.
- QuickTime X has also a screenrecord-feature incl. audio.
Lowcost solution: Specialized screenrecording software like Screenflick, Screenium, etc.
Prof. solution: Capturehardware like Ninja Atomos, HyperDeck Shuttle, Intensity Pro, Aja IO, etc. can record directly with ProRes-Codec.
Best DoktorHauser