You need some form of graphics software that will allow you to resize - Adobe Photoshop, Lview pro, Ulead Photoimpact are just a few. Then you do an image resize and make it into a smaller image (like if it's a 1024x768 image try making it a 640x480). Then if you save it in JPEG format there is a quality setting - you can turn it down to 5 and lose almost no quality but reduce the file size by about 10 times.