Hi Russell, i'm using a macbook pro. There are quite a few things you need to do to set up your mac to function the way it should while in linux. Here's a link to a websight that very good support for ubuntu and what you'd need, just go down and select the Macintosh computer that corresponds with your model and it will tell you all the steps you need to do and once that's all done, your computer should work right.
For a short answer to your question, the scrolling is one of the easiest things to fix.
go to the "system" menu. To "preferences" then to "mouse". Go to the "touchpad" tab. You want to untick the box next to "enable mouse clicks with touchpad" (this will stop the taping to click that you get with normal touchpads that's plain annoying with the mac pad). Then you will want to select under scrolling, the "two finger scrolling" option. That's it, your touch pad should be right now. Good luck (-: