Last night after rebooting my Mac it will no longer boot properly. After logging in I can see he desktop picture the menu bar and all of my startup items, but I do not see the clock or Spotlight. The Dock doesn't show up either. Finder does start but i can't do anything with it. I have access to the force quit menu where I can force quit Finder which will restart. Several other system shortcuts also work, such as reboot, logout and shutdown, but nothing happens when I click on any of the options. The screen and keyboard brightness keys also work but the volume keys do not. I've tried booting into safe mode but the same thing happens there. I also tried resetting PRAM and the SMC without any help. With the recovery partition I've repaired permissions and the disk but neither has helped. Is there anything else I can do or is my only option a reinstall?