available ram

This is a pic of my system specs.

Well, i called Microsoft support, and they told me the reason I cant use all of my ram is because my video ram is taking up that space. Is that true? Because it doesn't make much sense to me.

Click on START ->All Programs -> Accessories ->System Tools - > Resource Monitor ->Memory (Tab). Then a colour bar-chart and breakdown of all system memory is presented. Each section has an explanatory "bubble" if you hover over it (legend).

This should explain whether memory is seen or not, and how it is allocated.