DataGrid to new row or not to new row

I am using multiple datagrids bound to Tables in a dataset. I have been unable to force the addition of a new row to the dataset table unless another row in the same grid is selected. eg a new row entered on a datagrid, form closed, no data added to the dataset. This also applies if a different Datagrid is selected which makes it difficult to save added data.

However, assuming this is the state of things I decided to go with the flow and not allow adding in the grid but add rows separately, and just edit in the grid.

How do you make a grid not show a new row but NOT be ReadOnly?