Welcome to the forums gfordham.
What brand of dvds are you using? We recommend older style Verbatim AZO dye dvds and Taiyo Yuden, and Sony as a possible substitute when those two are not available.
What speed are you burning? Sometimes just slowing down the speed to 8x or 12x when using 16x media will solve this.
What process are you using to get the dvd video? Are you working from commercial dvds as your source or are these home made videos?
What is the make and model burner you are using? Do you bitset the +R disks? Bitsetting (also called changing book type) can sometimes help compatibility for burned +R disks. It isn't applicable to -R disks.