Welcome to the Forum jmfraz. For the most part, what you see is what you get when looking through the view finder of a DSLR. The rub is, that not all view finders on all DSLR's are the same. Some will show you 100%, other will show you a little less. So to answer your questions, the image you see in your view finder, is already "cropped", BUT it may be cropped a little more than what you will actually get. What this means is, that you may actually get a little wider view on your photo than what you saw in your view finder.

I hope I didn't confuse you. If you have more questions, let us know.