Accounts losing files and privileges

Does anyone know why Vista is losing the privileges? I have a standard and
an admin account and the lastest thing to just disappear is the privilege of
spell/grammer check in Word. I found the way to add permissions to the
registry, but this is not the first time. Files in Public have suddenly lost
permission to be viewed in standard. Is this a common occurance with Vista?
I've had nothing but problems since I set up the standard account. Somehow
programs are also getting installed on the Admin side and not showing up on
the standard user side. Please help! I have Home Premium and have been
fighting it for almost a year now.

Thanks