I know of at least eight Charlie Chan movies that are in public domain now, and freely available. I have also seen older, legal movies available through torrents, so just because Meron has obtained these through torrents does not make them off limits for discussion in these forums.
We will give him the benefit of the doubt.
Now, on to answering his question. Try using Audacity with the ffmpeg and Lame Mp3 libraries added in. You can find Audacity here: http://audacity.sourceforge.net/download/
You can find the Lame and ffmpeg libraries here: http://audacity.sourceforge.net/download/plugins
Once installed, click on File-->Open and navigate to your mov file. If the video format is recognized, Audacity will import the audio only. If you need to change the frequency, say your original audio is 48khz and you need 44.1khz, you can do that in the main window of Audacity at the bottom left.
You can then click on File-->Export, change the file type to MP3, and click on Options to set the bitrate. Click Save, and the audio will begin processing.
If Audacity cannot recognize the files, post again, and we can try a different tool.