If the records are in the db already like this then you will need to update them in the db. To do this you will need to search products and categories tables for the item or category and then update it when you find it.
Do you use phpMyAdmin for administering your MySQL db? This tool and most others have an option for you to browse or view the records in a table. You can do it this way and just find the product/category name and update it. For now you can just remove it then update it agagin in the admin area.
I'm also including updated copies of the categories_Results.php, Product_Update.php and Product_Insert.php pages for you. These pages belong in the Admin folder and can replace the default files in here. Make sure that you create a backup of your files first in case there are any problems.