On a Mac, i use Free Rapid Downloader. Just copy the youtube URL and start it. It downloads easily. Then, i copy it to a USB hard drive, and piug that drive into my Playstation 3 or Xbox One. You could also stream it from your computer via Plex, using either of these two devices, or the latest Apple TV. Not sure if the other streaming USB stick devices/Roku work with Plex, but i believe they do.
Making a DVD is an unnecessary (archaic!) step if you have one of the above devices. But, i imagine you could use HandBrake to convert the file to a format that can be dragged into Toast.