Make sure if you have Adobe Flash player installed in your computer.Follow these steps below,
1.Click on START button on windows,select control panel.
2.Open Add/Remove programs (win xp) or Programs and Features (Win 7) and check if 'Adobe Flash
player' is listed in the window that opens.If not,then you need to install it to run you tube and other
videos and animations from Internet.
3.To do so,please follow the below link http://get.adobe.com/flashplayer/
4.Now click on the big yellow button that says 'Download Now',it will take you to download page and download will start automatically,click on save to desired location.
5.Once the download is complete,open the folder where you saved the file and run the file named
"install_flash_player.exe",the Adobe flash installer will open,simple follow the instructions on
screen to finish the installation successfully.
6.Once its complete open your internet browser and check if you tube videos work,if you still have
trouble,let me know with more details and I will try to help further.Hope it helped.