As of March 1, 1989 a work is copyrighted the instant it becomes tangible. It is no longer necessary to register with the copyright office. However, it is still a good idea to file a work with the Library of Congress Copyright Office in order to give the copyright owner a stronger case in court and more money if someone infringes on the work. A copyright notice is also still a good idea because it discourages infringement, it forestalls a claimant's argument the he didn't know it was copyrighted, and it makes it easier to track down the owner to get permission to use it.
The proper form for notice of copyright is the word Copyright the date(s) and the author or owner's name. Some foreign countries still require the phrase "All Rights Reserved" but it is not necessary in the U.S. or signatories of the Berne Convention (see International Copyright below for more details). You could use the © if you choose instead of the word "Copyright" and for sound recordings regardless of format (e.g. VHS, DVD, CD, audio cassette)use the è. If you want to be more emphatic with longer statements like
"no part of this book may be reproduced in any format or by any means in part or in full without express permission of the copyright owner", etc, etc, etc. go ahead but, the only thing it might do is act as a deterrent to infringers; it really has no legal merit. What does have legal merit is that the notice should be noticeable; not hidden away in the fine print. The location of the copyright notice is legally defined as "in such manner and location as to give reasonable notice of the claim of copyright".
For more information on the Copyright Notice see Circular 3 from the Library of Congress Copyright Office.