PlayBack

The Combined Community Codec Pack is a simple playback pack for Windows with the goal of supporting the majority of video formats in use today. cccp-project.net

or



The K-Lite Codec Pack is a collection of DirectShow filters, VFW/ACM codecs, and tools. Codecs and DirectShow filters are needed for encoding and decoding audio and video formats. The K-Lite Codec Pack is designed as a user-friendly solution for playing all your audio and movie files. With the K-Lite Codec Pack you should be able to play all the popular audio and video formats and even several less common formats. codecguide.com

or if your feeling like a baller



Watching H.264 videos using Compute Unified Device Architecture (CUDA). NVIDIA Video Cards

Watching H.264 videos using DirectX Video Acceleration (DXVA). ATI Video Cards

Watching H.264 videos using DirectX Video Acceleration (DXVA). Intel ClearVideo