I've been trying to burn a video file to a blank DVD, then watch it on my TV. It's a lecture by a teacher.

I think I exhausted the (free) possiblities on my Dell laptop without success. Today I tried using Burn on my Mac. The burned DVD lays fine on the Mac, but again I was told by the DVD player (I guess) that the resolution was unsupported or that I must change the resolution of the external device.

I've concluded from my efforts that I must either convert the video file to a different resolution or buy a DVD player that will convert (upsample, upconvert, whatever) the file to make it watchable on my five year old (?) 43" TV. The DVD player is a Rotel and at least ten years old.

It has been noted in the past that 20% or more burned optical discs (CDs and DVDs) will be incompatible with any given player due to any number of factors including the specific dyes used in the disc, the specific frequency and power of the burn lasers in the burner (which change with time and use), the specific frequencies and power of the read lasers in the reader (which change with time and use), the material used for the reflective layer in the disc, and normal manufacturing tolerances. Read/write discs have a significantly higher failure rate than WORM (Write Once Read Mostly) media. That means your solution may require

1. a new burner drive
2. a new reader
3. a different brand or model blank media
4. some of the above
5. all of the above
6. none of the above

Since blank media is by far the least expensive item to switch out, the first thing I would try is a new blank disc and don't shop for the cheapest option. I haven't burned a disc in at least a couple of years so I cannot knowledgeably recommend a disc brand or model, but generally you get what you pay for.

You might also try on your Mac the free DVD burning app Handbrake. It has numerous setting options, some of which may meet your needs.