Have you heard of Scanner's Law? It goes something like the chance of the scanner jamming and eating your document rises in direct proportion to how rare, useful and important your document is. Just ask my sister about her birth certificate!
Save yourself a fight with your scanner by getting My Scans Pro. Just take a picture and it will automatically detect the edges of the page and save it as a PDF. You can then add multiple pages, rearrange them, edit them and keep them safe with its handy file manager. Normally $3.99, today it's $0.99.