All movies are in MPEG-1 format and also include sound. Keep in mind that it might take a while to download a file of 10Mb (say, 30 minutes).
Depending on your browser, a movie will either be played immediately after loading or only downloaded to your local disk. In the latter you have to open it in some sort of mediaplayer available on your system. If you do not yet have a player for MPEG, you can download them for free from the internet.