Hi
I'm afraid there is no easy answer to that. It's not only the content of those file which is important, but also order of them being added and this can be different for sites using same components. Best is to start from excluding biggest files like jQuery.js, mootools.js, etc and see if everything works correctly.
Good method is to list all the javascript files at once and delete one after another from the list while checking if everything is ok. Unfortunately it's a time taking method, so I would advice to start with big libraries and already minified once (usually has "min" in name).
