I've eaten in the three asked for twice each, Via Napoli once, and I would rate them in this order:
Tutto Italia -- "Real" italian food, as others have said. BY FAR best of the four. Excellent food both times we've gone. More expensive than the others, but worth it, or a good plus if on a
DDP. We were on the DxDP, but would willingly pay OOP for this quality food.
Tony's -- Olive Garden quality food, good and enjoyable, but not excellent, nice atmosphere for MK. Loud, but best sit-down you'll get in MK with the limited options.
Mama Melrose -- Also Olive Garden quality, more relaxed than Tony's, but between the two, I think the food at Tony's is slightly better. Would still go back again.
Via Napoli -- Pizza is decent, but they should sued for libel for calling anything else "italian food". I take that back -- for calling anything else "food." Everything besides the pizza was terrible. Will never step foot in there again.