What was the format of the download: MPEG, AVI, ISO? Did you do the encoding/authoring? Odd that it displays correctly on your computer, but not on your TV. That suggests to me the problem may be structural rather than the encoding as such.
If ISO, it's possible the IFOs were corrupted, and/or the IFOs and BUPs are not in agreement. Mount the ISO with Daemon Tools. You could try copying the VOBs and BUPs to a test folder, within which you have folders named AUDIO_TS and VIDEO_TS, put all files in VIDEO_TS, then rename the BUPs to IFOs. Burn to an RW and see if it works.
Or copy only the VOBs and VTS_xx_x.BUP to test folder, rename the BUP to IFO, open in DVDFab and create Video Manager (VIDEO_TS.IFO). See if that works. Or same as the preceding, but copy the IFO rather than BUP, then continue with DVDFab.
More drastically, you could extract the MPEG and check the AR in the latest GSpot. Then reauthor if okay. There are lots of other things to try, but I'd start there. Can DVDShrink open the video without complaint?