Question about recording audio on Vista

I’ve scoured my friend’s system trying to find this function. In XP you can use the default Sound Recorder program to record the sounds off of any playback-i.e. if I want to record some audio clips from a DVD I can just play the DVD, hit the record button on Sound Recorder, and no hassle. On Vista tho this functionality seems not to work (I get silence), or at least I have not found the Hidden Toggle ™ which would get this to work. Any clues?

When I want to record something off of the computer with Vista’s Sound Recorder, I use a cord my roommate has that plugs into the headphone and microphone jacks and and then I start recording. It works a treat and I don’t get any background noise from the other people yelling and slamming doors. I think the cord is a line in recording jack or something? When I’ve tried recording without it, the record is really quiet. Maybe your volume isn’t up high enough?