"Does anyone know where to download the original Microsoft mpeg-2 codec?" Which half and for what reason? Any co-dec has 2 parts a COder and a DECoder. If you can play a DVD on your system you already have the DECoder part. IMO MPEG2 is not a good solution for video. It is not that MPEG2 is bad, the problem is that it is more closely watched by because it is the DVD standard. MPEG4 is newer and better at achieving smaller file sizes at good quality levels. If file size is not a concern MPEG2 is fine.
Exactly what are you wanting to do? What is the source video? Where do you want to store/ship the final results?
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