Uh ... doesn't this belong on the 'Picture' board?
To reduce the size of images, the quickest method is to use the Paint program built into Windows. When a huge image loads in Paint, only part of it will be displayed. Click on the Image tool and select Stretch/Skew.
In the command box this summons, select Skew, and you will get a display showing the current dimensions at 100 percent tall and 100 percent wide. Change both to 25 percent, and it should fit in the screen. To send this smaller photo to others, use the Save As command to keep from writing over the original.
If you have windows XP ... this is even better:
http://www.microsoft.com/windowsxp/downloads/powertoys/xppowertoys.mspx