ffdshow is an open source codec that supports all major formats like DivX, Xvid, H.264, AVC, MPEG1, MPEG2 and many others. It also has filters for post-processing and enhancing the video quality.
Subtitles can be displayed as well, including those embedded in containers like MP4 or MKV. You can use ffdshow as an audio decoder too, but AC3Filter is way better in handling AC3, DTS or SPDIF output.
I have included a registry file that contains the settings I use to set ffdshow as the default decoder for all the supported files. It will display external or embedded subtitles and add post-processing to the video.
I use ffdshow, AC3Filter and DivX Tech Preview to play everything I want. You can use Haali Media Splitter along with DivX Tech Preview to support thumbnails of MKV files (just disable Haali thumbnailing feature to use DivX, which is much better). For video playback, Media Player Classic Home Cinema is my favorite.
Website & Download
Registry Settings
This codec package provides everything you need to view all major audio and video formats in Windows 7. For users that don’t want to keep looking for codecs and instead just focus on playing their files without problems, this is as easy as it gets.
You can use the player of your preference, including Windows Media Player and Windows Media Center.
This is the only codec package I would recommend. It is advised to install it on a system without any other codec packages, even when the installer can uninstall the most popular ones if it finds them. For support, there is a forum. If you have any doubt or a problem, you will find answers there.
Shark007, its author, has a version for Windows Vista users called Vista Codec Package that works as well as Win7codecs.

I use ffdshow, AC3Filter and DivX Tech Preview to play everything I want. You can use Haali Media Splitter along with DivX Tech Preview to support thumbnails of MKV files (just disable Haali thumbnailing feature to use DivX, which is much better). For video playback, Media Player Classic Home Cinema is my favorite.
Website
Download
x64 Components
ffdshow is an open source codec that supports all major formats like DivX, Xvid, H.264, AVC, MPEG1, MPEG2 and many others. It also has filters for post-processing and enhancing the video quality.
Subtitles can be displayed as well, including those embedded in containers like MP4 or MKV. You can use ffdshow as an audio decoder too, but AC3Filter is way better in handling AC3, DTS or SPDIF output.
I have included a registry file that contains the settings I use to set ffdshow as the default decoder for all the supported files. It will display external or embedded subtitles and add post-processing to the video.
I use ffdshow, AC3Filter and DivX Tech Preview to play everything I want. You can use Haali Media Splitter instead of DivX Tech Preview to support thumbnails of MKV. For video playback, Media Player Classic is my favorite.
Website & Download
Registry Settings
Vista Codec Package installs everything you need in order to play all audio and video formats. With this, you don’t need to keep looking for needed codecs.
It doesn’t come with a media player, so you can use Windows Media Player, Windows Media Center or whatever you like.
Totally recommended for those who want a codec pack that work right after installation without the need to tweak settings. If you want to configure settings, you will be able to do so. You can install it in Windows XP as well. For support, there is a forum.
Shark007, its author, has a version for Windows 7 called Win7codecs that works just as great as Vista Codec Package.
I use ffdshow, AC3Filter and DivX Tech Preview to play everything I want. You can use Haali Media Splitter along with DivX Tech Preview to support thumbnails of MKV files (just disable Haali thumbnailing feature to use DivX, which is much better). For video playback, Media Player Classic is my favorite.
Website
Download
Vista Codec x64 Components