Fastest way to convert MPG2 to MPG1?

[Redryder]

I have some huge MPG2 files (~20GB each) that I need to convert to MPG1 format. I tried Adobe Premiere Pro but it takes too long, almost 8 hrs per file. When I used TMPEnc it just crashed. Could someone suggest a better way to convert these files?

I already have a PCI realtime MPEG encoder card, is there some way I can harness the power of that card to do the conversion faster?

[lordsmurf]

First, why?

Second, TMPGEnc is probably fastest and can be one of the best methods if done properly.

[Redryder]

TMPEnc crashes as soon as I attempt to open my MPEG2 file.

And I need to convert to MPG1 for backup and archival purposes. The MPG2 files are simply too big.