http://www.denver.org/denverbeerfest
Cheeky Monk is a definite go to place.
Tom's is GREAT but only open on weekdays
Great Divide is downtown
Strange brewing Co. is close to downtown
Hops & Pie is a good place for great beers and good pizza (I skip the pies though and get their mac & cheese)
The Ale House at Amato's has good food and beer selection.
Stueben's IS FANTASTIC food.
Vesta Dipping Grill is great.
Biker Jim's Gourmet Dogs, delicious and open late. Great dogs like elk cheddar jalapeno dog, wild boar dog, all beef (boring)etc.
Really if you could give us an idea of where you're staying or what kind of food you prefer we could provide you great places to visit.
If you want a list I can PM you an extensive one I did for my cousing while he was out visiting.