This piece of software is great for playing most of the video formats as it supports a vast variety of codecs support in itself & just give it a try & u will surely love it and the best thing of all is that it's a freeware.
Formats supported are AVI,DAT, MPEG, DivX, MP4 & more.
Just google for it and it's a small download about 4 MB in size but also provides some of the advanced features. After using it for once you will find that it beats one of the most popular video player i.e. VLC media player.