Windows Vista - can not open anything

Not sure if this is a virus or what but...
Basically, I am unable to open any files or programs (not even task manager without logging out), it gives me error messages about not being able to locate the files/programs (ANY of them). Also, when I hover over the volume control in the taskbar it says "the audio service is not running", though I can not turn it back on.
Along with this, I also get the error message "you do not have permission to shutdown (or restart/anything else) this computer".

Is this a bug, a Vista glitch or something else?

Any help would be greatly appreciated

Thank you

 

Just competed the scan, it found nothing. Any other suggestions?
:confused

 

Oh, I found the problem. Comodo messed up somewhere along the line, uninstalled it and everything is back to normal.
Thank you very much for your help though :smile