LuckyPokeGirl, here's how most scanners work:
Generally there is a software program that comes with the scanner on how you operate it. First, connect your scanner to your computer, then follow the software instructions on how to scan a piece of paper. After it's scanned, it should save to somewhere on your hard drive (it will usually ask you where to save it).
From there, you can do with it what you can do with most any image - edit it, set as desktop background, upload to an online image client (like Tinypic or Photobucket), &c.