For sure you need to select the right output on your computer, in Windows that's often done by right clicking the desktop and selecting "Properties". In one of the tabs you can select an external monitor. Sound should work without changing any settings, try with a headphone first if your audio is switched on.

About the RCA plugs: red and white are audio, yellow is composite video.

Hope this helps at least a bit.

We use two different laptops at times on our tv to what online shows. One uses just the svideo and the other a hdmi. With either of those we do not need to use any rca cables. Sometimes it seems to be worth getting a newer tv. To complicate things, our cable tv provider is messing things up by requiring a box even for a digital capable tv. geez.

Casey
"Sean McDonagh Racing"

Why wouldn't you just buy a $99 apple tv? You could stream everything using your wi-fi wirelessly from your computer to your tv, including your photos, netflix streaming, your itunes etc etc.