I forwarded X over ssh. From unity-control-center I couldn't perform any of the administrative tasks like changing audio input, changing wifi network etc. How can I do them remotely. Its the same problem even when I connect through remote desktop. I think its some thing to do with policy kit. I could never remotely operate X since my introduction to ubuntu; Its 5yrs bck!
There is probably a couple solutions for things you requested.
VNC-server. Client-server couple actually. Allows you to control remote screen directly, to the active screen of the remote machine.
NX-server. Again Client-server pair. Allows you to have connection to independent Desktop with GUI, separate/different from the main screen (which is shown at monitor)