If its an unsupported stream, you should get a invalid file message. It will likely refuse to play it at all.
But to know for sure exactly what is supported, once you've decided on a TV & if it has DLNA, you'll need to look up its DLNA supported file types.
If, for example, it does not support DTS you have 2 options.
Recode the DTS Audio track to AC3 or whatever type is supported
Use a media server that can transcode on the fly, such as TVersity or Nero Media Home.
Both of these have a free version, which streams your media as is.
The paid versions are the ones that can transcode on fly, so it would be an additioanl expense.
However, it would be easier & cheaper to recode the Audio track to a format that is supported by the TV.
Simply because, unless you are using a High End Home Theatre, you will not likely tell any difference between DTS and higher bitrate AC3.
But thats getting into something entirely different than Plasma vs LCD/LED ..
So Ill try not to derail anymore
All of this is pointless unless you decide you want a TV with this feature anyway.