I never thought about using EPS. I've used PDF for all my school projects up till now, taking them to Kinko's as needed (low file size and good quality there). 300 DPI is an industry standard and usually looks the best. Colors are a pain in the ass, and if possible convert to CMYK in Photoshop. CMYK is the colors printers use, Cyan Magenta Yellow and Black. (who the hell represented black with a 'k'?)