Problem with saving documentsi n Word 2000

I use XP and Word 2000. Sometimes when I save a document, especially if it is a revision of something, it appears in the Save list as having a tilde and a dollar sign instead of the first one or two letters of the title, e.g. ~$iver Twist. Then when I click to open it, it appears as a complete view including space indicators, of my name and address, and the left column that describes the item says Attributes: Hidden

This has previously happened very occasionally, but it happened yesterday every time I tried to save and then reopen a series of revisions of an entire sequence of 13 separate documents.

Has anyone else had this problem? I can't think how to look this up in my Word reference books., so I'd appreceiate any help you can give me.