I onced burned video files directly to DVD-R, but it can't be played on my home DVD player. Later I learned that if one want to play the DVD on home DVD player, you need first convert video files to DVD format, which is in form of "AUDIO_TS", "VIDEO_TS" and then burn them to DVD disc, so then you can watch it from dvd player on TV.
I often use X2X Free Video to DVD converter and X2X Free DVD Video Burner to achieve this purpose. You can get this two small freeware here: http://www.x2xsoft.com
I hope my experience can help you avoid detours.