#1. "RE: Software for putting a border around the photographs and signature" In response to In response to 0
I don't know what free programs are out there.
If you have Color Efex Pro for Capture NX you can achieve this by applying the CFx Vignette filter, select the last filter shape from the drop down list, minimize the transition so you get a hard edge, set the opacity to 100, adjust the size as appropriate and select whatever color you want. It does fit inside the boundaries of your image, or the crop if you have cropped it. Because of that, it works best at providing a relatively narrow border, rather than the look of a wide mat.