Mexican food at the Morrison Inn (301 Bear Creek Ave) in Morrison (WSW of Denver).
Big game dinner at the Buckhorn Exchange (1000 Osage St, Denver) near downtown Denver.
Denver Art Museum
16th Street Mall
Red Rocks Amphitheater
Denver Museum of Nature and Science
Estes Park / Rocky Mountain National Park
Hit the casinos in Central City
Play tourist at Aspen or Vail.
I'm not a local, so I'm sure that this is just the tip of the iceberg.