Should I watch these anime?

Well, out of all of those, I've only seen Madoka Magica. I highly recommend it, it's one of the best animes I've ever seen. The música is gorgeous, as well as the plot and characters. The series is fairly short, but there are filmes as well! I really think it's a must-watch for all animê fans, even if they aren't fãs of Magical Girls.

Sorry I couldn't really help with the others!

ive only seen D. Gray Man and Deadman Wonderland. But i do highly recommend them :)

Well you should definitely watch xxxHOLiC, D. Gray-Man and Deadman Wonderland since they're great anime. I wouldn't know about the others since I never saw/heard the other animê listed here.

Higurashi and Higurashi no Naku Koro ni are actually the same anime. Well, I would reccomend the aforementioned series, xxxHOLIC, and Puella Magi Madoka Magica.

I would recommend leitura the mangá versions of Pandora Hearts, Deadman Wonderland, and D. Gray-Man to that of the anime.

The only I would NOT recommend is Higurashi.

And I've never seen Deadman Wonderland so not sure about that one.

But the rest are really good and you should definitely watch them!

I would DEFINITELY recommend watching XXXHolic and D. Gray-Man