Creating hires jpg pics

I have been asked to take a high res jpg picture of a piece of equipment . The pic is for use in creating a display stand of approx 15x4 feet. I have a camera that will shoot in RAW as well as jpg. I need to know if I need to adjust my settings on my digital camera (NIKON D80 SLR) in order to create HiRes. Thank you for any help offered.
Pat