Is this graphics card compatible with my PC?

Yup, it will work just fine. The graphics card plugs into the PCIe lane, which is the long thin plug. It's pretty self explanatory once you see the graphics card.
Basically, when you get it plugged in, just plug in your hdmi/dvi/display port cable that you use for your monitor(s) into the graphics card(not the motherboard like it is now). And youll need to go onto nvidia.com and download the latest drivers for the card.

But hardware wise, it is 100% compatible.
EDIT: Whoops, you'll need a new power supply...
 


Okay, cool.. So I just upgrade the power supply, install the new card.. and I'm set?
 


Just make sure you plug in all the right cables ;D

Also, you'll need to download drivers for the nvidia card. That's really easy to do. A simple "nvidia drivers" google search and you're set. Here's the page you'll be looking for though: http://www.nvidia.com/Download/index.aspx?lang=en-us
 


Awesome! Thanks a lot!