For the best quality, scan them big! 600dpi @ print size (8.5"x11" is a regular page size). That makes for a really big image file that would take a while to download. You may end up paying for the download time and storage space... If the printer prints at 600dpi then you're looking at a nice quality. As for color management, that depends on the system that is being used, but photoshop comes with color management.