This depends entirely upon your over all purpose and the architecture that you would like your application to be based upon. there are so many CMS available like Wordpress, Joomla,
Wordpress is very popular. A choice of CMS depends upon how knowledgeable you are with a particular CMS. Is there a support from some company, are there paid templates, what are your expansion plans for your website and so on
Have a look around among the available ones and take a decision . Wordpress is a good choice I hope other members agree?