For upscale dining, Bistro 157 is really excellent as is Dish restaurant. Both are American-style, and both have menus online:
dishrestaurant.net and bistro157.net
Don Quixote is also tasty, and serves authentic Spanish food both in tapas style and full size portions. While we love the food, the tables can be fairly close together, and they often feature music. It's a much livelier atmosphere, but not conducive to conversation.
donquixoterestaurant-in.com but no menu online
There are 2 relative newcomers on the square: Pikk's Tavern, also American style but with sandwiches as well (and a tasty brunch), and Paparazzi, serving modern Italian. The atmosphere at both is relaxed and casual. Pikk's menu is also online (pikkstavern.com). A word of warning about Paparazzi: service can be very uneven. We had a great lunch on a very slow Sunday afternoon, but were treated quite rudely on a Friday nite. But the food was good and menu extensive.
I wouldn't recommend Strongbow, unless you just have to have some turkey. And then I believe I'd go to the grocery before I went there -- it's just dry, tasteless turkey at its worst.
If you go to Porter, be sure to try Santiago's -- their homemade mole rivals the best in Chicago.
And if you need a pizza, Tony's in Valpo is legendary.
Enjoy the vale of paradise........!