I would think color backgrounds would scan well. I scanned old 35mm photos on a cheap scanner, and they look good.
OCR, optical character recognition, using a comptuer to automatically converting a scan into characters, sentences, paragraphs, etc., that you can then edit or search.
old magazines: black characters on a white background, easy for an OCR to convert (if its on high quality paper, yellowed newsprint, not so easy)
new mags: mix of black and white characters on various colored backgrounds, doesn't covert well at all