if you're going to be anchored in denver, here would be my list. I went to school in Golden for 4 years.
if you're in town on april 8th, i would head up to my alma matter for the edays fireworks. Nothing like it. Here's what to expect: a football "stadium" that junior high kids in texas would spit on, more fireworks than the queen of england orders up on her birthday and dynamite. School of Mines Campus-Golden.
as suggested earlier, if you drink or not, coors brewery. Golden.
If you do drink,
Golden City Brewery. It's the 2nd largest brewery in Golden, and the bees knees. 12th St, Golden.
Red Rocks, as suggested earlier. I prefer to enjoy on matthews winters. a 4 or so mile loop, excellent vistas.
while you're in morrison, eat at
the fort. by far my favorite place to eat in the area. who serves bone marrow besides the mongolians?
i would skip any 14ers. unless you have crampons and alpine boots. and you're in decent shape. 70 degrees at 5000' doesn't mean nice weather at 14k. get any hiking done before noon if you're in the mountains.
all the city stuff denver has to offer. which doesn't interest me much. just going and looking at their rei is amazing, if rei is your thing.
you could try RMNP. not too sure how it will be...
skiing. there's a novel idea. go to colorado and go skiing. a basin is usually good to go until the 4th of july. you can even swing over loveland pass.
that's my quick and dirty. i'm jealous. have fun.