A family of Microsoft word processing software products for creating web, email, and print documents.
If you're referring to trying to delete a file in the Save (or Open) dialog, you can't do that - Apple discourages that type of behavior. You need to delete files in the Finder.
If you're seeing your file icons turn gray on your local drive in Finder, that usually indicates that their Hidden property is set. But you still should be able to drag them to the trash. If you aren't, use the Disk Utility to reset disk permissions to allow you to access your files.