Typically how much time/hours do you spend there? I'm thinking whether I should get a one-day pass or two-day.

We went there one day. And didn't get to ride all the rides. Two days would be better.

When we went there, we were only there for half day(noon-6) and didnt get a chance to see or do everything. If you get there when it opens, and be there til closing, I'd say you'd have enough time.

We did one full day in the oark and did the preview the night before.

Depends on number of kids, what day u attend and tolerance for crowds and lines.