If you wish to Add/Remove system generated columns in SharePoint designer (SPD), you need to first open up the site in SPD then open any view’s aspx file.
In design mode, you need to right click on the DataFormWebPart and select “convert to XLST data view”.
Now you should have a “Common data view tasks” popup, if not, just click on the arrow to the right. You could then select “edit columns”.
Select single column (which you wish to delete), right click on the column and select Delete Column. You desired columns will be deleted.
Now you will be able to add/remove columns in SharePoint Designer Save the file when you done and your SharePoint site will be automatically updated with the new columns.
If you have any concerns/queries do let me know.
More details on Data Form WebPart