|How far is your TV from the room your computer is in? You might be able to get a range extender or directional antenna for these devices.|
but we would need to know what frequency the device works on.
Personally, I would just build a Media Computer (with BlueRay and surround sound) for your TV then use remote desktop or VNC, to remote control that computer from the other computer. This way you can store Music and Movies on that computers hard drive without having to waste space on your primary computer.