DataGridView - how to hide the "new" row?

On the form designer view, click the little arrow to the right on the DataGridView. Adjust the value for Enable Adding. That will remove the row at the bottom of your grid.

Programmatically, you can adjust the AllowUserToAddRows property.

myGrid.AllowUserToAddRows = False

Just a clarification for other people who are looking at this for WPF the datagrid property has been renamed to CanUserAddRows

The DataGridView has a boolean property AllowUserToAddRows. Set this to false and you should no longer see the empty row at the end of the grid.