Speaking of Media Player Classic, for the longest time (haha, I just realized I just repeated myself), I have also wanted to tell Windows Vista to disable the screensaver. It was annoying that whenever I was using Media Player Classic, it would start the screen saver after 30 minutes into the movie. I would then have to disable the screen saver temporarily and re-enable it afterwards. Similar with turning off the screen and sleep/hibernate options.
Anyway, while I was searching for something recently, I came up on Media Player Classic – Home Cinema. It appears to be a fork off the main Media Player Classic branch and one of the things it supports now is: Kick off Screen Saver from Power Options only while video is playing (Vista). So if you’re a fan of Media Center Player and dislike the fact your screen saver goes off when the video is playing, you should check out this Home Cinema version.
Open the vedio player ….the path may differ from player to player
for media player.
Click Tools> Options> under player tab you will get the option for: Allow screen saver during playback
Uncheck this option and click Ok.
In VLC player the path is different.
Click settings, then Preferences, then General Preferences, then Video. Then choose Disable Windows screensaver when playing video under Video Playback.