Why don't you setup a separate 'test' area?

You should have a 'test' area anyway so you can test things. For example, setup a test store then Export the database. You can then see how things should be. Make changes, Import the changed database and see if anything broke.

Most any Spreadsheet can open a 'csv' file, which is a format phpMyAdmin will allow you to use. Excel has given many people problems I suggest using http://openoffice.com/ which is free and since using it, I have never needed to purchase or use MS Office.