One thing, what has "OS (C:) program files (x86), as this was 'grey'" have to do with downloading a document? Documents are downloaded to your personal files or the desktop.
Also Program Files folder should not be greyed out unless someone somehow has placed restrictions on the machine. This sometimes happens when a machine has been part of a Corporate environment or on a University Campus, to mention just a couple of examples.
If I were you I'd get it looked at by a good PC repair shop to sort out such anomalies.
Otherwise I'm glad things are OK.