Had a good Gyro at Cusmos in Lindenhurst. French fries were nice and crisp, too. Unfortunately, the Tzatziki sauce was not that great and I'd pass on the Greek salad, but definitely try a gyro and fries. You can eat there if you don't mind the old, faded plastic tablecloths.
Cusmos Greek American Restaurant
200 E Montauk Hwy # D,Lindenhurst,NY 11757
Phone: (631) 225-8797