MacBook F12 & eject keys no longer function

Hi,

I'm getting frustrated with my MacBook, I've never had any problems with it until now. Since watching a DVD on the laptop's superdrive, the F12 and eject keys are no longer responding.

It first came to my attention whilst trying to use my F12 key to see my dashboard. I use the dashboard often so I used system preferences and checked my keyboard shortcuts and mission control to ensure the appropriate settings were selected. Nothing there had changed. F12 remains the key to open and close the dashboard and the function key is not having an effect. The other keys still operate as usual (show desktop, application windows, etc.). I have tried using the console command "Killall Dock" but this hasn't resolved my problem either.

I am using the hot corners function and the eject.menu shortcut for the time being but I'm hoping to get these keys working again as it will affect the resale value of the machine. Has any one got any tips or help that will resolve my issue? I don't believe that any damage has occurred to the machine as it is very well looked after.

Thanks in advance!

MacBook mid 2007
OSX 10.7.4

 

It has also come to my attention that my plus and minus key as well as my dash and underscore key aren't functioning. Is this just my keyboard beginning to breakdown or is there a possible software problem?