The Loop is easily walkable, and you'll probably do all that.
Start walking up Michigan, past Magnificent Mile, up into the Gold Coast. Nice apartment neighbourhood. Take the Red Line up to Wrigley Field, and walk around the gay part, and Andersonville.
Take the Blue line out to Ukranian Village and Wicker Park -- very nice, Toronto-ish neighbourhoods. Good bars everywhere.
I was just in Chicago, and made two pictury posts on the Spacing wire about places we wandered, that might give you some ideas:
spacing.ca/wire/?p=963
spacing.ca/wire/?p=968
Do make sure you get out of the downtown, and see the real chicago. Too many people just stay in the centre and come back to TO thinking what we do here is garbage. Chicago has a lot of catching up to do outside of the pretty areas, much more than TO.
You can do the nieghbourhoods i mentioned on the El....Chicago is huge though, and a car might be requires.
Had lovely runs in the evening up the gold coast and around Grant park.
We stayed at a boutique hotel in the 1895 Reliance Building....very nice, not too expensive...$150 a night or so. but such a hot building (first steel skeleton and all that).
www.burnhamhotel.com
But reserve lots of time to wander and just find stuff.
For sure for sure take the architecture tour i mention in the spacing post....the boat one like us, or one of the others ones that you'd like. so worth it.