I would not think that VirtualBox would be faster. I think so because, it is sharing resources with your second OS (chances are it is Windows).
Basically, I would recommend doing an actual installation instead of VirtualBox.
However, if you need WiFi, VirtualBox is the only way it will work, because your WiFi Card is not compatible with Mac OS X (No intel cards are compatible).
Your NVIDIA card will not be compatible either. But intel HD should be fine