Autoptimize plugin works perfectly for JS / CSS / HTML minification. The following settings are recommended:
Please consider that depending on third-party plugins installed to your WP, settings might require appropriate reconfiguration. The default “Exclude scripts from Autoptimize” JS settings are: “js/jquery/jquery.js”.
And for CSS are “wp-content/cache/”
This plugin can be used together with W3TC (it allows to enable gzip compression, configure headers, etc.). In this case, you need to disable “Minify” in W3TC.