Honestly I just sat here and read the whole case and digital code paper and it says nothing about that. Also I know that HD means high definition but I am not sure what SD is but my tv that we play the DVD on is an HD tv.
I don't ever and have never used a digital code out of any of my movies. I normally just auction them off on here when I find them in the case. I have never even been asked any of these sorts of questions before and I'm not sure how to answer you other than it say to go to foxredeem.com. It also says that after you enter the code you can select your preferred service to redeem your movie.
If you know that your code came from a DVD I would always advertise sd. But if you know it is HD I would definitely put that in the title because usually HD goes for a lot more.