Save any images that you scan, or any photographic type images, in jpg format. For general purposes, you want an image to show in its entirety, in one screen. In other words, you don't want the average viewer to have to scroll to see the whole image. I use 270 pixels as a rule of thumb, for the maximum length  (At 72 dpi, this is 3 3/4 inches). I generally keep the width to under 400, although it can go as high as 575 without scrolling horizontally (if there is nothing next to it).

Sometimes you will want to reduce a whole image, and sometimes you just want to crop it (take a section of the image).

To reduce an image in PaintShopPro, open the image, click on Image, Resample (Resize if it is a gif image, or for either format in version 5.0) then input the new size in the screen that opens. If you "Save as" another name, it will leave your original intact in case you need it later.

To crop an image, use the rectangular "selection tool". Double click on the point in the image that you want to be the upper left hand corner of the new image, holding the mouse down on the second click, drag the cursor down to the lower right corner of where you want the boundry of the new image and release the mouse. You will see a rectangular dotted line over the new area. If this is not correct, right click to erase it and try again. When you have the portion selected that you want, click on Image, and Crop. You will now have only the portion of the image you want to use.