It might be a bit annoying when your screensaver kicks in while watching videos, movies. But you can disable or stop screensaver from activating by using any one of the free and simple taskbar applications mentioned below. This way you can stop screensaver from coming on while watching movies.
Stop Screensaver from Coming On While Watching Videos, Movies
# Caffeine (Link)
If you have problems with your PC locking or going to sleep, caffeine will keep it awake. It works by simulating a keypress once every 59 seconds, so your machine thinks you’re still working at the keyboard, so won’t lock the screen or activate the screensaver.
The icon is shown above – it’s the leftmost one in the task tray, and this is all you see. Double-clicking the icon empties the coffee pot (that’s what the icon is) and temporarily disables the program. Double-clicking it again refills the pot, and will keep your machine awake and helps you disable screensaver while watching movies or videos.
# Mouse Jiggler (Link)
Mouse Jiggler is a very simple piece of software whose sole function is to "fake" mouse input to Windows, and jiggle the mouse pointer back and forth.
Useful for avoiding screensavers or other things triggered by idle detection that, for whatever reason, you can’t turn off any other way; or as a quick way to stop a screensaver activating during an installation or when monitoring a long operation without actually having to muck about with the screensaver settings.
Simply run the MouseJiggle.exe included in the release .zip file. Check the "Enable jiggle?" checkbox to start jiggling the mouse pointer; uncheck it to stop. The jiggle is slight enough that you should be able to use the computer normally even with jiggling enabled.
The ‘Zen jiggle?’ checkbox enables a mode in which the pointer is jiggled ‘virtually’ – the system believes it to be moving and thus screen saver activation, etc., is prevented, but the pointer does not actually mov
Similar, freeware application Jiggler keeps your Mac from going to sleep at inopportune times.