Max Shutter speed
Casio EX-ZR800 can shoot continuously at max speed of
3 fps and has max shutter speed of
1/2000 sec.
Flash
Unfortunately EX-ZR800 doesn't have an external flash shoe so you are limited with the built-in flash.
Focusing
Casio EX-ZR800 features a Contrast Detection autofocusing system.
Casio EX-ZR800 also features
Face detection AF where it intelligently detects the faces in the frame and locks the focus automatically.