Option 1 (delete). So long as the pages exist there's a need for someone to manage them and I am uncertain that is outweighed by their historical value. Just because something can be saved, doesn't mean it should.
One of the 15 freaking hats I wear is file server administrator. It's not my job to manage the files, but the server operation. File servers are used as a dump for anything someone thinks might be of value to someone else someday. When that "someone" leaves for other employment (every 3 years, roughly), the files sit there unnoticed forever. Even if someone does notice them, they're afraid to delete them since they aren't their files. Then people have conniptions when the server runs out of space and suggest buying another server to hold everything.
In short, my experience informs me it isn't a good business practice.