If management asks you to write down how you feel about the company both positive and negative, would you be afraid to spill your guts about what is working and what is not? I feel that people get canned anytime they do this and not sure if I should do what I was asked.

Many companies these days do things like this as part of risk assessment. So my advice is to be sensible and don't put everything in there and the kitchen sink. If there is some true cracks where things are falling through then say something. But be constructive about it and not just negative. Keep a positive outlook and spin it with a possible solution.

I personally would never do it, where they would know who it is.

I would only do it, if it can and was done with no names attached.