Professor McGonagall is her usual strict, somewhat uptight (but still quite loveable) self in the film. She is always willing to lay down the hammer with students, but she's also fiercely protective of them.
When Harry gets entered in the Triwizard Tournament, for example, she's super against having him compete:
DUMBLEDORE: What do you suggest, Minerva?
MCGONAGALL: Put an end to it. Don't let Potter compete.
DUMBLEDORE: You heard Barty; the rules are clear.
MCGONAGALL: Well, the devil with Barty, and his rules—and since when did you accommodate the Ministry?
SNAPE: Headmaster, I, too, find it difficult to believe this mere coincidence. However, if we are to truly discover the meaning of these events, perhaps we should, for the time being, let them unfold.
MCGONAGALL: What? Do nothing? Offer him up as bait? Potter is a boy, not a piece of meat.
Yup, for all her toughness, she's clearly very worried about Harry's safety. It would give us the warm and fuzzies…if we weren't so busy also being worried about Harry's safety.