Here’s how–for Mac, Windows, and Linux;

With kJams (Mac): Right click on videos, click “Export QuickTime” and choose a destination folder. You need to register ($40) to convert more than 10 videos at a time. Video quality is great.

With Power CD+G to Video Converter (Windows): Also costs $40 to register; not useful in trial mode.

With cdg2video (linux): you’ve got to build it yourself, no Ubuntu packages, only Gentoo ebuild. Free as in freedom, baby.

With PyKaraoke (Windows and Linux): There’s a “convert to mpg” option. Haven’t tested it, but if it’s broken they’ll fix it.

Now, there should be a way to do this for free on all platforms with VLC. VLC is supposed to be able to transcode any format it can play into a range of formats (including Quicktime, h264, etc). Plus it’s scriptable, so if you can convert one file, you can convert a whole library.

But I tried all the options I could think of and couldn’t get it to work. The resulting videos would play in VLC, but with errors in iTunes. Ableton Live must’ve picked up on those errors in its pre-analysis and wouldn’t even try to import them.

Right now I’m happy with kJams, so if anyone finds the magic parameters, let me know.