With Vista Codec Package installed, you won't need to install any other codec or filter. Many user suggested default settings are implemented. It does not contain a media player. It does not associates filetypes.
With this package installed you will be able to use any media player (limited only by the players capabilities) to play DVD's, movies and video clips of any format. Streaming video (real and quicktime) is supported in web browsers. Visit the homepage to get a 64bitAddon which enables xvid, divx and DVD playback in Vista's MediaCenter. x64 Components addon
Vista Codec Package (and x64 Components addon)