If you're just outputting through the headphones port, then yeah, just get an 1/8" to RCA splitter, and make sure they're long enough to go into one of the amp channels.
Normally when you ask this kind of question the tech needs to know all about your laptop. The more the merrier.
Red and White just represents the left and right audio. It's just a standard.
Your sound quality may suffer depending on the audio card that you have in the laptop.