The so call vga to rca cable only work if your computer has tv out through the vga port. In your case i'm pretty sure it don't. So the vga to rca cable will not work. What you need to get is a vga to rca/s-video converter box. They run between $20 to $30 CAD and works perfect.
They will work on any computer with a vga out that works. and also has another vga out loop on the box to hook up another vga monitor.
Heres a link
But you still need to buy a audio cable to get the sound to the tv.