that I know is possible, but I would like to have Ubuntu first, since the whole computer will be safer from hacking/slashing/backing and horses and so on =)
But the drivers for OSX are pretty good.
The drivers for Ubuntu are available at best and not even that at the worst. Thus it really is the better idea running OSX and the other stuff on top of it.
What are you so afraid of hacking anyway. OSX is as secure if you use it sensibly and but the safe guards in place. It is both Unix thus in essence the same.