Individual scenarios, yes. Each big box kicks off a campaign with a particular theme: Runelords is classic "goblins and ogres and zombies" stuff, S&S is pirates, WotR is a demon invasion. If you like the first two adventures that come with the box--each adventure consists of ~5 scenarios, typically three play sessions--you can add on adventure boxes that extend the campaign until an ultimate conclusion several add-ons out.

If you want roleplaying, I imagine you'll have to check out the Pathfinder roleplaying game adventure paths the ACG boxes are based on!