screen saver vs turn off monitor setting for LCD monitor

I have a Samsung 17 " SyncMaster 174v monitor. Even with a very low
brightness level when I use a blank screen screensaver setting, when the
computer goes into screensaver mode, there is a very noticeable glow on the
screen. By comparison if I use the turn off monitor setting and set it for a
short time like 1 or 2 minutes when it turns off, the screen goes completely
black with no visible glow at all. Is it therefore better to use the turn
off monitor setting after a minute or two rather than using the screensaver
with blank screen setting for the same time interval ? Is the some kind of
strain on the monitor when using the turn off monitor setting. By contrast
is there some kind screen burning/dulling by the persistant glow when using
the blank screen screensaver setting ?