I'm not in Colorado any more and its been a few years so....
My favorite eating places were:
Tommy Thai (downtown area, good thai)
Jerusalem's (late night middle eastern food near DU)
Heidi's deli (good deli with good bread)
Indian (there were a few places I liked but overall I thought the Indian food in Denver was decent - I'd look for a place and go)
Can you do any walking/hiking? Rocky Mountain National Park is nice and there are hikes of varying degree. Also, you can drive to the tree line which I thought was nice but if you aren't used to the altitude, it may make you sleepy
Boulder is a funky little town to walk around in. The celestial seasonings tea factory tour is pretty cool, I've done it at least twice
I recommend it to anyone who visits the general Denver area.
There is 16th street mall downtown Denver which you can walk around and see various shops. For more nature type things, Red Rocks park is also pretty unique and fun to walk around just to see. It is also quite a drive and a little late in the year for tulips but I thought driving up to Vail was fun. There are small shops which you can visit and the drive up there is kind of amazing.
Any particular interests?