YouTube videos are Flash Player videos and your internet browser should not be using any other player like Quicktime, WMP, or Real Player to play these. In fact I wouldn't have Real Player anywhere near my computer.
But I'm confused because you say the videos play but then halt for 20-30 seconds with the spinning circle. If that spinning circle is within the video window itself and is not your mouse cursor spinning, then that means the video is 'streamed' to your browser and the browser is waiting for more data to be downloaded. That should only mean that you have a slow internet connection.
If you do have a slow internet connection then there is little that can be done.
I cannot play You Tube videos..They start and stop constantly..little circle will spin for 20 to 30 seconds at a time..i dont know enough about this to do anything..what kind of video system am I suppose to be using??It says to make sure Quicktime,Windows Media and Real Player are not my default player..what is suppose to be??Please help me because i dont know how to fix this...