Maybe a new user for Windows 7 didn't know about this one. It's called Snipping Tool. You will find this tool in accessories folder in start menu. You will see this icon.
You just need to click it and you will get a pointer to point from where to where location on your desktop need to be captured. So, you don't need to print screen your desktop and editing for your need. Just click, drag the area, then finish. You can save it or directly use it with your document or anything else you want. But just in case, I suggest to save it for another purpose. That's all, I hope you will find an easiest way to do print screen your desktop. See you in the next post.