What are the requirements hen building a new computer from scratch on the DVD Drive? Do I need special software to be able to read the Windows 7 CD? Do I need a Sata cable for the Drive to function?
The drive will function normally right out of the box. No special considerations are required. But yes, you do need a SATA cable to plug it into the motherboard.
Retail comes in a retail box like you would get from a store with a manual and accessories (if there are any). OEM is just a bare drive that comes in a brown box with nothing else.
Retail should come with a SATA cable, as well, where OEM will not.