The movie's tagline (which you can see on the image in the main page). "When a girl has a heart of stone, how can you melt it? Just add ice." You might just let the nonsense of melting something with ice pass considering it's a pun, but how can you melt something made of stone?
Technically possible with some stones, although large amounts of heat are required. It just makes the statement even more hilariously wrong.
When she first sees Ice's motorcycle, the old lady tells her husband that it's worth more than their house. So...does that mean their house is next to worthless, or are we supposed to believe that the motorcycle is worth hundreds of thousands of dollars?