All three places are very different.
Lula is in the Logan Square neighborhood, about five miles northwest of your hotel. It's a bit funky in style (think waitstaff with tatts and piercings), and the food leans towards local and seasonal ingredients.
one sixtyblue is on the Randolph Street corridor, two miles west of your hotel. The food is contemporary American, the decor contemporary. I've found it to be pretty good since Chef McDonald took over in late 2008, although not as good as under his predecessor, who is now continuing his culinary magic at Cafe des Architectes (where I would choose over any of these three).
Shanghai Terrace is a luxury version of Chinese food, and in that way is quite unique. It's in a top-notch luxury hotel (the Peninsula), a half mile north of your hotel. The food is very good, and the service is exquisite.
I haven't been to any of them on Valentine's Day, so I have no idea how they might be different from usual. Normally, Shanghai Terrace would be a bit more expensive than the others - figure $100 per person including moderate alcohol, tax, and tip - and one sixtyblue would be the least, maybe $60-70.
You can have a nice, enjoyable dinner at any of them.
HTH