OK, So I finally crawled back behind the TV to remind myself what model I have.
It's a Samsung LN-T4665F
I played around with some of the settings in the menu and no luck. With my model I can't select the input directly. It only allow me to cycle through the available inputs and it refuses to see that the PC (HDMI1) is a valid input when the signal is connected.
I have not been able to try the HDMI cable yet because the one I have has too much extra plastic around it to go into the port on the PC because of mechanical interference with the case I'm using. So, I either need to buy a smaller cable and return it if it doesn't work for me or modify the case. (Time to get the Dremel humming