Play/Pause/Next/Previous functionality doesn't work using keyboard/remote

Question

I have recently upgraded my 24'' iMac to a 27'' i5 iMac and migrated my information via the Migration Assistant using a gigabit peer-to-peer (crossover cable) ethernet connection. Since then or shortly after the play, pause, next and forward buttons on the keyboard stopped working (or they never worked, I am unsure).
Moreover, the same functionalities when accessed using the Apple remote also does not work, note that the volume up and down buttons do work from the Apple remote.
I am also having difficulty getting my digital camera identified using the USB interface but that is another show. The camera is not even seen by the Image Capture tool in the Utilities, note that I succeeded once in getting it identified but not since then. The only change I can remember was installing the MouseWizard tool for extending gestures of the magical mouse, which is probably the finest thing I have got from the whole upgrade (the most easily appreciable). Please ignore the matter of my digital camera, for me mentioning it only for the slight possibility that it may be connected. To this humble users they are two things that are not working at all. Some of the applications I have installed is Parallels Desktop 4.0, which seems to identify the camera once connected but not the Mac OS X system.
Thanks in advance for your generous help.

Answer 1

Today I made a brave international call to Apple in the USA, realising that less than 90 days has passed since I purchased my new iMac. The phone call lasted for 62 minutes and was utterly embarrassing and genuinely awkward for me as it was totally unhelpful and very, very costly. The guy on the other side was very unable to provide any meaningful help and it was not easy for me to tell him that he was not, so I had to go on with the costly call which was mostly filled with moments of silence and contemplation (and forgetting -for the thousandth time, that my keyboard is wireless, telling me one time after the other to try to unplug it from the USB and connect it again).
Anyway, I am delighted to have discovered the problem myself, which is amazingly simple, and unbelievably responsible of both of the two (seemingly unconnected) problems I was having (the problem with the functional keys on the keyboard and the identification of my digital camera).
The problem was simply solved by deleting a textual file from the root of the home folder which is the file called ".CFUserTextEncoding". I have no idea what this textual file stores (a string of the form "X:XX") and how could the four bytes in it be of so much annoyance in my case, but deleting it can bring the media control keys back to life and make the digital camera identify effortlessly. Quite puzzling I would say.