The link given above by Malainse is a good one for your problem. One link there is to Image Resizer ...
http://download.microsoft.com/download/whistler/Install/2/WXP/EN-US/ImageResizerPowertoySetup.exe
This program will probably do what you want to do. If not, re-post here and we will find you something else. The size of the photograph can be looked at in two different ways. One, physical print size, i.e., 8x10 or 5x7 or 4x5, etc. The second is number of pixels, i.e., 680x350. Depending on where the "problem" occurs you might want to try reducing the number of pixels in the photograph. If you change to much the image quality will start to degrade and details will be lost.
Confused yet? [
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