Many times I have tried to download YouTube video with Real Time Player. This application offers you that option but in many cases I get video without sound.
After some research for that problem I gave up and decide to look for better solution.
So, if you want to download video from YouTube using MS Windows this is right application for you – YTD Video Downloader. Now I am using this application and I can tell that it is quite good for its purpose.
To download video just install this application and do steps like paste YouTube link, setup download folder and some other options like video quality etc…
In case your OS is UBUNTU or some other Linux OS then I recommend this method for downloading video.