I strongly disagree with the list. As many horror series as I can come up with here now:
1. Buffy the Vampire Slayer
2. Angel
3. Dark Shadows
4. Twin Peaks
And I kind of dawdle off from there. I love Buffy and Angel because of everything about them; the characters, the mythology, the plots, the level of intelligence... yeah, everything. Dark Shadows I place at #3 because, for all my gentle poking at the show (or outright mocking in the case of a few areas which I won't go into here), I really, really like the show. It's not as good as Buffy by any means, at least in my opinion, but you have to consider what they did. Buffy and Angel together racked up 266 damn fine hours of television over 8 years; DS managed to do over 600 of generally good quality in around 5. Speaking of damn fine things, #4. I feel Twin Peaks was probably a better show than Dark Shadows, but I find Dark Shadows far more endearing, and this is my favorites, not what I think is the best. The X-Files and Death Note make honorable mention due to me not having seen all of them but knowing that I basically like them. If I saw all of them and liked them as much as I have what I've seen, I'd probably slide Death Note into #4 and The X-Files into #5, knocking Twin Peaks down a bit.
Those are really the only six horror shows I've watched to any extent, not counting anthologies like Tales from the Darkside and The Twilight Zone. I've watched shows with various degrees of the supernatural, from Lost to Beauty and the Beast to Charmed, but I wouldn't consider any of them horror shows. I definitely feel DS deserves to be higher up on the list than some of the shows on there, particularly shows like Friday the 13th. I've never liked "wanderer" shows where the main character(s) are off on some sort of adventure that has no real meaning in the grand scheme of the series; they're anthologies under the veneer of true series. But those are just my opinions.
And calling DS dry is a bit ridiculous. Even when they were repeating past storylines, like the ghost of whatever couple it is this year, or in a rut, like during HoDS's filming where every episode began with Barnabas's chained coffin, as if to say, "Here he is!", the show didn't feel dry to me.