I personally have been disappointed in Salpicon and would not recommend it.
Lovitt is a small, intimate place (reservations STRONGLY suggested) which I would highly recommend. Would require driving as it is not in the Loop (on Ashland just south of North Ave) but the food is great, the space small and intimate and they specifically feature at least one vegetarian option for the non-meater in your party. The menu changes weekly based on seasonal ingrediants.
Yoshi's Cafe is another restaurant I have never been disappointed in, located up in Lakeview, it too would require some driving from the Loop but they do have valet and is well worth it.
If you are eating out this week or next, take a look at
www.Opentable.com and look at the "Dining Out Chicago" promotion. 15+ some Chicago area fine dining restaurants offering special $35/person menus for dinner (and some a $20/person lunch) with some of proceeds going to charity and with a free bottle of Pelligrino included in the price (Pellegrino is one of the sponsors).
My girlfriend and I are going to Le Lan on Monday to enjoy the special - by making our reservation online, we'll also get 1000 "opentable points" which basically means a $10 gift certificate for future dining. All in all a great deal (and a bargain for most of the restaurants participating) and a fun evening out. Might be a good option for your outing.
Cafe Spiaggia would suggest itself as one very good option. Le Lan perhaps another, but look over the full list, many of the sites are quite good.