Your PC probably has a free PCI Express slot and a free PCI slot.
Your Quadro card is probably PCI. Judging by the size of the card, I don't think it draws much power... you should be able to use it without upgrading your power supply.
Now, here's the tricky part... those Quadro cards seem to come with a variety of video outputs. If yours has DMS-59, you will have to buy an adapter to use it with DVI displays.
The Quadro card supports two displays.
You will have to disable the integrated graphics to use the Quadro card.
You need an adapter if your video card has the DMS-59 connector... here is an example of what you're looking for: http://www.newegg.com/Product/Product.aspx?Item=N82E16812200206&Tpk=DMS%2059%20to%20dual%20DVI
You can probably find these for less if you look around... just make sure you have the right kind of cable.
If one or both of your monitors needs to be connected via VGA, you can buy cheap adapters to go from DVI to VGA.
Hope that helps.