The address for Stone Road Grille is 238 Mary St. and just to check I used mapquest to come up with 1.32 mi for the distance. It's up to you, but for most people that might not fall into the walkable category.

Also, where you're staying might determine whether you might want to drive too.

Next door to the theatre is Zees, the Buttery is along the main street, as well as Ristorante Giardino in the Gate House for Italian.

http://www.gatehouse-niagara.com/

For fine dining the Oban Inn and the Charles Inn are walkable. But for more choice of dining rooms, a few minutes drive will also take you to many of the wineries. La Cachette at Strewn was wonderful last month!

http://www.lacachette.com/

Hope that helps.