PowerPoint didn't work very well for this. So, I decided to re-explore Adobe Captivate. I used Captivate a lot at my last job and kind of hated it. I think it was version 4 then, and now 6 is out. It's like all Adobe products - lots of options. Although I used it a lot, I never felt like I really knew what I was doing. However, it has gotten better and now it publishes into HTML5 so it's accessible on iOS devices.
The biggest advancement in Captivate, to me, is it's integration with PowerPoint. You can do most of the work in PowerPoint - a much more user friendly environment - and then pull it into Captivate to add the buttons, branching, and quizzes. While you're working in Captivate, you can edit in PowerPoint and then go back to Captivate. Then it publishes into a Flash/HTML5 video so it plays much more consistently than it did when we were just using PowerPoint.
Another cool thing about Captivate is that it can create roll over captions, which means you put your mouse over something and then info pops up about it to explain a bit more. A very user friendly option for this functionality is Thinglink, but Thinglink is pretty much a stand-alone deal, whereas these Captivate roll overs can be incorporated right into a tutorial.
Captivate also does a great job with quizzing right in the tutorial and it now offers some advanced interactions like Articulate.
I haven't used it a lot, but I made a video showing what I know now about adding click boxes, buttons, and roll over captions. You'll probably want to make it full screen. It is in HD but takes a minute to focus once in full screen.