If you have a sound blaster soundcard you can use the Creative Recorder to get the audio from the game, but it'll also record sound effects etc, so you should stand still when you're recording. If you dont have a sound blaster card then you can try Total Recorder, which usually works well, but the shareware version has a limitation of 40 secs or so, so you might need to do some edititing to get it all together. There should be plenty of apps at
www.download.com, but in my experience some of them are rather bad, so you'll just have to investigate yourself. I also recommend you get the trial version of a wav editing app, like Steinberg Wavelab (or whatever it's called), so you can remove what you dont want.