Your best bet would be to Google all these audio codecs, so you can get familiar with them, and understand where they coming from and what they do.
Briefly, DTS is better than DD, because it is less compressed.
Blu-ray discs can be encoded with Dolby TrueHD, or DTS-HD MA, or DD, or DTS. Or a combination of some of those.
From your Toshiba DVD player, you can only get DD and DTS. It depends of the DVD disc itself; some are encoded with DD, others with DTS. And very few, have both.
You are not a moron, only the ones who believe they are, are.
* Take care & use Google to get some knowledge on all these various resolution audio codecs. There are certainly quite a few of them.
Bob