Acrobat 8 Scanning Problem: Lines turn jagged

Hi all.

I hope this is not a dumb post, I am not well-versed in technology and have been trying to solve this problem through experimenting with the settings to no avail.

I'm trying to scan in documents (mostly text, some graphics) through Acrobat 8.1.1. I'm encountering formatting issues with the final scans in which lines turn jagged, text becomes less sharp, and faint jagged lines appear at the top of the page where there is only blank page.

Does anyone know how I might solve this issue?

Really appreciate the help.