If you want to ensure a payoff, come hungry and spend most of your Franklin on food. That’s why I decided to determine the best way to drop $100 during an evening there. Though Rivers probably still doesn’t need my business, you’ll be hard-pressed to find a nicer spot to gamble in Illinois. Or at least it didn’t the day after its July 17 opening party, when the new gambling mecca just east of O’Hare Airport (3000 S River Road, Des Plaines, 88, ) was so crowded officials asked people to delay visiting.