Well, to make things easy for you, I would download Google's
Picasa, install it, and it will display all of the pictures on your computer. Find the ones you scanned, and once you go to File > click "Save" and it will ask you if you want to resize your picture. After you have your resized image saved, go to any free image hosting website, like
ImageShack, and upload your picture.
From there, grab the link you want and then paste it wherever you want to put it on the internet.