I don't know how the scan procedure works (yet), but I have the following (boxed) games:
Addams Family, The (PAL)
FIFA International Soccer (PAL)
International Superstar Soccer Deluxe (PAL)
Lost Vikings 2, The (PAL)
Magic Sword (NTSC)
Rival Turf! (PAL)
Samurai Shodown (PAL)
Super Street Fighter II: The New Challengers (PAL & NTSC)
T2: The Arcade Game (PAL)
WWF Raw (PAL)
Flatten the box absolutely flat.
Put the box on the scanner bed absolutely straight.
Put heavy hardcover book on the box, it should be bigger than the box but smaller than the scanner bed.
add some extra weight.
Scan 600DPI, moire removal on.
Upload to Mediafire or Box.
Post link to the image on the boards.
Before scanning all your boxes, scan one and post the link here so we can tell you if something needs to be done so the scans will be perfect.