Etrigan's fire is magical and Superman is weak to that. There was no way for him to stop the fire with his hands. I liked the book.
Are you saying he shouldn't have tried to stop it with his hands or addressing the part in "the bad"? If the latter, I was saying he could have saved the Lanterns by punching, tackling, or using his powers other ways to knock Etrigan (and that would mess up his aim), and given how he's been acting in the series, I'm surprised he didn't take that route.