Update, i'm trying it on the Vista PC now, and in Audacity, i gotta use the Microsoft Sound Mapper - Input option in the Recording device list when having the headset plugged in, it works just fine, with Windows Live, i gotta use Microphone (High Definition Audio Device), even though there is two of 'em, one works and the other doesn't, with Steam, it's the same thing
Here's the Sound window

Edit: Oh wait, Line In is the ports on the back of the PC? If so, the ports on the front of the Vista PC works fine, but the Laptop doesn't have that, only the ports on the side, i'll have to mess with stuff again