mrmatty......... Well ,after looking at the pics you provided .......I would think that what you have is a prewired house for both internet and sound . What I cant be certain of is the card ( board) a terminal point only or a router or hub .........
I would also think that there is probably a place for a incoming cable ( or telephone ) connection . If the board is just a terminal point then you would need a 4 port router , the router outputs would plug into the appropriate output2 ( LAN 1 , 2 ,3 , 4 or 5 ) depending on which rooms would have a pc .........
Then if you were using a HS cable connection .........a cable modem would be plugged into the incoming cable connection and its output , would plug into the incoming plug on the router.
Then at the other end ( the appropriate room ) a cable from the wall jack to the ethernet card on the pc .......
However , if this is a new house ..........talk to the builder and they should be able to give you more info .....or perhaps the realtor .
Btw , I was unable to find out anything by searching the numbers on the card ........
Let us know what you find out .
dl65