Had one very nice pre-theatre dinner at Thalia. Nice salad to start, and shared some delicious soft shell crabs (sorry about the lack of detail -- it was a few months ago). Would definitely go back. I'm anxious to try Vice-Versa, though!
Have eaten at Vice Versa a number of times and even had a private party there last year on a sunday afternoon. It has been excellent every time. A cut above any other pre-theatre place and a place to go to even if you're not going to the theatre.