when i create videos with Windows Movie Maker i see often on the left and right side is a black room, i want to know how i can make this to be without black free room, the picture should be visible in the complete.
Look for example this video:
You can see left and right side sometimes is there instead of the picture or video to be on complete site visible.
Surely that black space is simply because the original video is not in the same aspect ratio as the YouTube viewer? Making it full width would either distort the image, or enlarge it so that the top and bottom are no longer visible.
The black bars are due to Aspect Ration Difference between the original video and your output.
The output have aspect ration of 16:9 (your uploaded video).
The aspect ratio of the video/photo with black bars is 4:3.
If you make the video/photo full screen you will lose a significant portion of it, top and down parts will be cut off.
I would leave it as it is, or find a different footage that has 16:9 aspect ratio.