Since my first post on 5/30 regarding the Themes problem, I was able to restore my default Theme settings by setting up a new user profile with full privileges. This somehow gave the new profile a default theme. This also gave me back my default themes on my profile as well. I then deleted the new profile and everything remained back to normal.
This also corrected another "Theme" problem in which I was not able to save or rename a newly created theme done on Vista using a different desktop background or sounds. The downloaded .theme files really did a number on my original Theme Vista program and my advice is live with the themes that come with the factory settings.
I have Dell Chat Support which is free for 1 year with my Inspiron. Dell could only advise me to pull out the Vista DVD and reinstall it. I'm glad I didn't jump at their suggestion.