twisted, welcome to the forum.
Sorry, but you can't connect a digital coax signal directly to the X-530 system.
The X-530 only has analog inputs, and those are the three minijacks that you'd normally connect to a PC soundcard. One minijack is for the front right and left speaker signals, one minijack is for the rear right and left signals, and the last minijack is for the center and subwoofer signals.
To connect you TV, you would connect the headphone jack (I'm guessing a minijack) to the minijack on the X-530 for the front right/left speakers. The other three speakers wouldn't get used. If the TV has a digital coax plug, well, you can't connect it to the X-530 directly. That coax will be outputting a digital signal that is encoded, and the X-530 has no ability to decode it. You'd need a separate Dolby Digital decoder, and it would make more sense just to by a system that can use that digital signal already (for example, the Logitech Z-5450 system).