Make a Simple Matte
The easiest way to create a frame is to surround your photo with a solid background. In Adobe Photoshop Elements 6, choose Image, Resize, Canvas Size from the menu and then add some extra "padding" to the picture. A simple way to do so is to click in the menu and choose Percent, and then set the width and height to 110. Click in the color box and select a shade that suits the photo--I tried a rosy hue. Click OK to exit. If you don't like the size of your frame, you can always click Undo and try again with a different value.
As you can see, you can use this technique to create a built-in matte, and then print and frame the result. Or you can use the border as a completely digital frame for your photo, even if you never plan to print it.