Grazie a tutti per l'interessamento, ecco il codice:

codice:
    Private Sub DataGrid3_MouseUp(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles DataGrid3.MouseUp
        Dim myhitinfo As DataGrid.HitTestInfo = DataGrid3.HitTest(e.X, e.Y)
        If myhitinfo.Type = 1 Then DataGrid3.Select(myhitinfo.Row)
    End Sub

    Private Sub DataGrid3_DoubleClick(ByVal sender As Object, ByVal e As System.EventArgs) Handles DataGrid3.DoubleClick
        Dim pt As System.Drawing.Point = DataGrid3.PointToClient(Cursor.Position)
        Dim myhitinfo As DataGrid.HitTestInfo = DataGrid3.HitTest(pt)
        If myhitinfo.Type = DataGrid.HitTestType.Cell Then
            Dim cliid As String
            cliid = DataGrid3.Item(myhitinfo.Row, 10)
            Try
                OleDbDataAdapter5.SelectCommand.Parameters(0).Value = cliid
                DataSet81.Clear()
                OleDbDataAdapter5.Fill(DataSet81, "persone")
                TextBox23.Text = Format(CDbl(TextBox23.Text), "#,##0.00")
                TextBox24.Text = Format(CDbl(TextBox24.Text), "#,##0.00")
                DataGrid3.Enabled = False
                Panel1.Enabled = True
            Catch ex As Exception
                MsgBox(ex.Message)
                MsgBox(ex.ToString)
                Exit Sub
            End Try
        End If
    End Sub
I campi video sono agganciati con un binding (es. dataset81 - persone.idagg1 per la label che ha il problema)