Try this code.
Private Sub grdCreditPDS_SelectionChanging(ByVal sender As System.Object, ByVal e As GridSelectionChangingEventArgs)
If (e.Range.Contains(GridRangeInfo.Col(1)) Or e.Range.Contains(GridRangeInfo.Col(2))) Then
e.Range = GridRangeInfo.Cells(1, e.Range.Left, 32, e.Range.Right)
End If
If (e.Range.IntersectsWith(GridRangeInfo.Cells(33, 1, 128, 2))) Then
e.Cancel = True
End If
End Sub