Download VCDGear which is a freeware. This will let you extract the video from VCD as an .mpg file.

Another freeware AoA Audio Extractor will then extract audio from .mpg file. This software claims it can extract audio directly from .dat (VCD format) files but it did not work for me. So I had to first convert VCD files to .mpg files using VCDGear and then extract audio from the .mpg file.

if you search the net, you may find some software that will directly extract audio from VCD files. Let us know if you find anything like that.