Which codec to use

I am making a video out of a powerpoint presentation for distribution, I was concerned about which codec I should use to encode it so that it is viewable on the majority of pcs. Any suggestions?

MP43/MP42 (fourCC) aka MS MPEG-4 VKI Codec v3/v2 works on about any computer that has Windows Media Player 6.4 or greater installed.
//Danne