You can download the you tube video to your machine and then insert it as a video in your presentation.
One of the sites I like to use is called KeepVid. But be warned, you do NOT want to click the big misleading buttons that say "Download". The link to actually do that is on the far right of the field where you provide the YouTube URL. Once you click the button, you will then be provided with several formats and sizes of content to download.