Next, you must install a DVD decoder. Even though DVDs can store 4.7 gigabytes, the data of a full-length uncompressed movie would not fit. So, the Moving Pictures Experts Group(MPEG) came up with a compression scheme called MPEG-2 that allows the compressing of moving pictures and associated audio at broadcast quality. MPEG-2 allows a full length feature film and audio to be stored on a DVD.
There are two types of DVD Decoders: hardware and software. Hardware DVD decoders are for older computers with processors slower than a 500Mhz Pentium II. Hardware decoders offload the process of decoding the DVD from the CPU, freeing it up to handle other tasks. Modern computers have CPUs fast enough to handle decoding DVDs while completing other tasks simultaneously. To help this process, Microsoft introduced Directx Video Acceleration(DXVA) which allows software video decoders to take advantage of the hardware acceleration found in most newer graphics cards thus saving valuable CPU processing power.
There are many MPEG-2 decoders available. Cyberlink, DScaler5, InterVideo, MainConcept and NVIDIA PureVideo are just a few which range from $15.00 to $50.00. Purchasing and installing one of these decoders would enable Windows Media Player to play DVDs, however, there is also a free alternative: the K-lite Codec Pack. The K-Lite Codec pack comes in 5 variations: Basic, Standard, Full, Mega, Corporate, and 64-bit. The Standard edition of the K-lite Codec Pack will enable you to view DVDs in Windows Media Player. You can download the K-Lite Codec Pack Standard edition here. Once installed, reboot your computer and Windows Media Player will now be able to play your DVDs.