I saw something on Wiki on the Dark Shadows Tim Burton movie page. Tim Burton said himself that the end (spoilers don't read if you haven't seen.) The end where the doctor opens her eyes was for the nature of the soap opera part. Tim Burton said in that case there won't be a sequel but you never know.
Yes, because if they do then he will get more fans and there will be a lot of people that will watch it, especially since the first one was a big hit. It is honestly my favorite movie. And i think he will make a great Barnabas Collins