Dan,
Thank you for your forum post.
In the customize tab select the Tables/Fields tab link and find the Opportunity table.
In the Opportunity table, where the field was added, if you dont wish the 'Name' (Opportunity Name) field to be required you can un-check it there.
If you havent added pre-defined values in this field, you can add them here as well.
NOTE: The field will have to be deleted and then re-added to add values to the dropdown.
Please advise if more information is needed.