Yes I need a Dvd Decoder Compatible With Windows Media Play
Download the latest version of Windows Media Player. Go to Tools, open Option and in the File Type tick DVD Video or better still, all files shown there. Another good option is VLC Player, it can play almost all media files. VLC Player is a freeware and the file size is only about 20 MB. Somewhere in Blurtit, some people recommended Cyberlink PowerDVD, but this is not freeware. Version 11 is about 88 MB and version 12 about 113 MB. I suggest installing all audio and video codecs. K-Lite Codec Pack is the best one available as of now.
If you use VLC you will still need to download a decoder. I recomend sonic cineplayer if you are using a HD graphics. I believe it's about $30, but worth every penny.
There are many out there to download however I would recommend the K-Lite Codec Pack - www.codecguide.com (download from here)