Always happy to help when I can!
I recall surveys back in the late 90's when those first came out, and it seemed like 50% of the people preferred DD, and 50% preferred DTS. So...it was a toss up.
DTS is less compressed than DD, so it can in theory have better sound quality. Whether it will or not depends on how the audio track is mastered. It also matters whether someone's equipment (including their ears) can tell the difference.
All that said (too much, probably
), I prefer DTS. I do think that it sounds better on my system. My suggestion, which you are probably doing right now, is just to try both out and see which you like. Be sure to try it on more than one disc, as it can depend on how the audio was mastered.