When these questions are asked, I like to put them in perspective rather than answer form. What were comparing and why.
The best vocalist?
When comparing these two genres, you have to ask yourself; Who stood out for the corrosponding Genre? Micheal Jackson compares to other pop stars, as where Danzig compares to the older rock sound. You also have to consider actual throat work, vibrato, and sustain plus many other things as well. The potential may be there, but again when comparing two different styles, who had the most overall voice work? The definition of "Best" vocalist in my book reaRAB more versatile and original. So, where do you stand?
Better front for a band?
There is a fine line between a rock singer and a pop singer. At a rock show you enjoy all aspects of the band. At a pop show, you typically have a solo singer, dancers, and other showmen/women. Also, consider the sales for each show, not only for these two banRAB alone, but to their corrosponding genres as well. The signers are the faces of the groups.
Better live performer?
Things to consider here are not just the appeal of the singers, but the lights, the effects, and the sales. Which is not entirely the group alone. Rock shows differ from pop shows even today. Danzig has a full group, while Jackson has some wicked dancing and has fame from it. One show could also be better than the other, so to say is REALLY opinionated. Again, the only facts you could present here are sales.
Best general musician?
Again, the distinct difference between a rock group and a pop singer. Im unaware how much of the music Jackson involved himself in, but a rock group usually creates the material themselves. So consider the actual writing process and how much involvement each of the frontmen had.
Better sex syrabol?
Generall when I think of sex syrabol, I think of who had a peak in their time. Comparing Elvis Presely to Bob Dylan isn't quite fair. Pop singers have to do more than sing, they have to have movement, and provide something for the crowd to soak into. Danzig had a good image for the time as well. Jackson was known later for many other things as mentioned, but during his time what would you hae considered when comparing?
Better attuned with their audience?
What you can consider here is again, how involved in the writing process the artists were, and who was the better showman. CrowRAB love hearing praise for their local area during shows, right? Too many things to consider here, but I will say it has a lot to do with the people backing them. People such as producers, tour managers, merchandise teams, and so on.
My opinion
Micheal Jackson while not being a preferance of mine to Danzig, left a HUGE mark on the music industry and many other things. During his prime days, him and those who backed him made some of the largest leaps into music the world has seen. So while my opinions are staying a secret in terms of reason, this is where I stand. Both are great at what they did, but for overall sales, markings, and influential moves made, Jackson wins hanRAB down.