Things to do in Denver (when you're *not* dead)

Just a quick note - I'll be in Denver for just a couple days in mid-May, arriving on a Sunday afternoon and departing Tuesday afternoon. I'm staying at the Hotel Teatro and should be settled in by about 4 Sunday afternoon. I'm looking for something to do Sunday evening - a good place to eat, a knitting shop that will be open, a must-see museum/attraction/play, a quiet spot to sit and have a cuppa and dessert, whatever - preferably within walking or easy public transit distance from the hotel. There's also the possibility (assuming the hotel will let me stash my bags there after check-out) that I'll have three or so hours Tuesday afternoon before I have to leave for the airport, so ideas for that time slot are also welcome.

And while I'm at it, I'll be in Kansas City in early June and Long Beach, CA in mid-July, so suggestions for not-to-be-missed places for those are welcome, too. The stay in Kansas City is several days and will include several free evenings, so multiple options there are especially welcome.