Batch editing of MPEG1/2 files?

[onewaydown]

I have a crap load of movies that I need to change the audio from 44hz to 48hz. I'm doing it right now with TMPGEnc by de-multiplexing the video, re-encoding the audio, and then multiplexing them back together. This works fine other than the fact that I have 20+ gigs of files to do. I don't need, or want, to re-encode the video. The process I use now is fine, I just need some way to automate it so I don't need to sit here for hours doing each individual file. Anybody have any ideas?

Thanks a lot.

[onewaydown]

anyone?