The closest restaurant nearby is Petterino's - like 1/2 block away from the theater. It's nice, but I wouldn't call it romantic. Other good places within a block or three are Atwood Cafe (which is romantic - probably as nice a view as you'll get in a ground floor restaurant), 312 Chicago and South Water Kitchen. You are going to have trouble with $30 per person and still be "nice." You might come pretty close at these last three places but not with liquor. Another place I like nearby that is more moderately priced is Nick and Tony's. All the steakhouses mentioned above and the Ritz Dining Room will be WAY over your budget. You can do a Google search for any of these places and get an idea of menus and prices.

BTW, Wicked is great! Feel free to PM me with any questions. I live within walking distance of all these places.