FormsCentral purpose is to gather data. If your job description is also a form (e.g. people can apply to the job from within this job description page) then you can use FormsCentral. The online form will always have a submit button so it you are not asking for data then it will look weird to have a submit button after your job description.
You can also use FormsCentral to create a static PDF (without a submit button). For that you either need Acrobat Pro XI which come with FormsCentral for Acrobat OR you need to have a paid account since generating PDF from the FormsCentral website is a paid feature.