The two videoclips are identical but in different formats. If possible, choose the 
*.WMv version, which is of the smallest size and best quality. If it does not work
for you, chose the *.MPEG version

Just click on the icon, and it should play.

If you are unable to play any of the videoclips you should update your windows mediaplayer 
(http://www.microsoft.com/windows/windowsmedia/mp10/default.aspx)