If you haven't yet decided, I would highly recommend La Parolaccia. Not walkable from the Westin, but a short car or cab ride. Great thin crust pizza, excellent pasta, and a perfect Chowhound restaurant.
If you want closer, Ringo's 1st two recommendations are definitely appropriate.
Two Italian restaurants that are short walks from the Westin are La Traviata and L'Opera. Both are quite good. A short taxi or bus ride away (small red buses, line A) is a more highly regarded Italian restaurant, Michael's on Naples, which might fit the foodie definition better than the other two
101 Pine Ave., Long Beach, CA 90802
301 Cedar Ave, Long Beach, CA 90802