As I do for, when I click the Modify button bring the data from a row of the DataGridView to the fields above and also if I save as inactive leave the row as Enabled = false.
txtCodigo.text = dataGridView.Rows[indiceDaLinha].Cells["nomeDaCelula"].Value.toString();
To name the same thing.
For the Radios you do:
if(dataGridView.Rows[inicideLinha].Cells["nomeDaCelula"].Value.toString().Equals("Inativa"))
{
radioButtonInativa.checked = true;
}
You may need to make some corrections to the name of your components. But that's how I would do it.