It may very well be that you're running Windows on a Mac. The typical PC and Apple keyboards may look the same but have different functions, and this in turn could be throwing off your game when it comes to the controls. Windows may be easier to use than a Mac's standard platform, but it might be best to get Windows off of your Mac, or maybe find a Windows Keyboard system file to install so that your PC reads it as a Windows keyboard and not an Apple keyboard.
Some links you can look at that talk about the differences between the two keyboards and their functions:
Difference between Apple and PC keyboards (http://xahlee.info/kbd/apple_pc_kb_diff.html)
Comparing Mac and Windows keyboards (http://www.dummies.com/computers/macs/comparing-mac-and-windows-keyboards/)
The Apple Keyboard - Compared to the PC Keyboard (http://www.computer-hardware-explained.com/apple-keyboard.html)
This is about the best I can do, I'm not familiar at all with Macs, in fact I dislike them, so I can't offer much help.