One place is http://www.zamzar.com you can convert YT into many formats, for PPT I would suggest .avi or .wmv
>From M$ 2003 PPT Help: "On the Insert menu, point to Movies and Sounds, click Movie from File, locate the folder that contains the file you want, and then double-click the file. Note A movie or .gif file that you've added to Clip Organizer (Clip Organizer: Microsoft Office program that contains drawings, photographs, sounds, videos, and other media files that you can insert and use in presentations, publications, and other Office documents.) is found in the Clip Organizer folder within the My Pictures folder on your hard disk. Or, go to the original location for these files. When a message is displayed, do one of the following: To play the movie or GIF automatically when you go to the slide, click Automatically. To play the movie or GIF only when you click it, click When Clicked. Note If you try to insert a movie and you get a message saying that Microsoft PowerPoint can't insert the file, try inserting the movie to play in Windows Media Player."
