Whatever works. If your talking about a computer screen you'll just have to play with the settings, both on the camera and the computer screen until you get them to match. You'll know that they match when the black rolling bar disapears.
It isn't the shutter speed you need to adjust -- it's the sync rate or scan rate. You'll find it in one of the menus on the camera. You can adjust it on the fly and see the scan lines of the computer slow and stop.