Macbook not letting me open my HD! And other issues

I'm not new to Apple products but I am new to this site.
A little rundown on my Macbook:
Early 2008 13"
10.7.2 Lion
2.4 Core 2 duo
4GB

I do not know if this problem started before or after Lion. For some reason I cannot open my harddrive. I am typing this from my Mac, and I can use everything installed on it, but I cannot open the HD and browse folders and such.
Also my camera would sometimes stay on and I couldn't get to turn off.
When that would happen I would do a PRAM reset it and the camera problem stopped. Sometimes the PRAM reset would allow me to access my HD but not all the time.
My final problem is that my macbook will not let me update my iphone. I can and have updated iTunes, and everything else about it works fine. The guys at my local Apple store worked on this problem for 2 hours and couldn't figure it out. This problem has been going on before the iPhone 4 was released.

Any help would be awesome!

Did you try booting the machine to the Recovery partition and from there open Disk Utilities and run a verify - repair on the hard drive?

Yeah I have done that. It didn't help me access my HD.