I'm not entirely sure what you're wanting to do? - is it to use this monitor as your PC monitor?.
There are a number of problems with this, firstly the resolution of a video monitor is FAR! less than a PC one - so picture quality is likely to be far inferior to a proper PC monitor.
But more importantly, the specification is COMPLETELY different - a PC monitor works at more than twice the line frequency of a video monitor, and often more than three times the field rate.
In order to do it, you first need to run your PC at a low resolution (often only VGA 640x480), and have a video card that will output a video signal.The video card contains the hardware to do the required standards conversion, which never works terribly well!. Personally I've always had loads of trouble making them work!, and when they do the picture quality is still pretty poor.
As for the two sockets on the monitor, they could be for various reasons? - often you have a video IN, and a paralleled socket for looping OUT to another monitor. Or they might even be video and seperate sync inputs?.