Go next September instead?
Obviously, I'm kidding, but basically the closer it gets to Halloween, the bigger crowds Scarowinds is going to pull. Since you haven't gone yet, I'd go as soon as possible so your waits aren't as long as they would be otherwise. As far as attractions go, it really depends on whether you'd rather spend most of your time riding coasters or walking through the different scare zones. Regardless, I'd get to the park as soon as it opens and immediately head towards Afterburn (unless you really want to ride Nighthawk). The reason being that people will generally flock around what they see first (Nighthawk, Intimidator, and all the scare zones close by) as well as the biggest attraction in the park (Fury 325). The area Afterburn is in is far away from the main entrance and is on the complete opposite side of the park from Fury, so there shouldn't be as many people in that area. However, if the South Gate is open, there might be people coming in near Afterburn, in which case you may want to head towards the Carolina Cobra area.
With that said, if there's a specific attraction that you really want to experience, go there immediately. It might mean longer waits for everything else, but I guess you'd have to decide what your priorities are.
EDIT: Also, Saturdays are by far the most crowded day to go.
