the ending
For me the car ending up in the river was totally unexpected so it was really fun.
HOWEVER would have been much better if they did not kill the croc, that is so stereotypical and unoriginal, may be that they do manage to swim to the shore and then you see the croc swim away and the movie ends there.
killing him was weak, he is a croc he did nothing wrong he did what a croc does it's simply humans who should not have been there.