does rails display user friendly error messages automatically

I am debugging a application and i see one setting as

config.consider_all_requests_local = false

in config/environments/staging.rb and a 500.html file in public directory.

So if the status in header is 500, does rails display 500.html automatically? or do i need to make additional settings so that if exception occurs display 500.html

i am using rails 3.1, any help on this will be appriciated