I move them to paint and then click on Image and then stretch/skew. After you shrink it and save it to a file, you can then right click on it and it will tell you the size space it takes up under properties. For pictures from Kodak digital, I need to go down to about 30%, you may need to go another percent. There may be an easier way but I have limited computer skills.
The easiest way is to just download them onto a picture website that automatically downsizes them for you. This also will not take up valuble Hamb space. Go to Photobucket.com A great place to store them. After downloading simply right click on it and get the adress and paste it on a reply or post here.