Saturday's are very busy for Halloween Haunt, I would recommend buying Fright Lane to get front of the line for the haunted houses, if that's your goal. Or fast lane if your goal is the roller coasters. The park is open 11a to 1a, but the houses don't open until 6 or 7p. The outdoor one's might not open until 8p. I enjoy Halloween Haunt a lot, the houses aren't all that "scary", but with that being said, I have been going every Friday night for the last 5+ years, so I have the houses laid out and know what's going to happen next.
Thanks! My hubby and I were just there 2 weeks ago so I got to ride the coasters then but we'll definitely look into the passes. With it being said, I love being scared to death and we all love going ghost hunting when we get a chance.