Moving a WP install and site from a sub-dir to the root on my server

Hi,

I am thinking of moving my WP install and site from a sub-dir to the root on my server, it currently resides in a directory called wordpress, from what I have read if I want multisite, any further sites would be sub directories of the existing wordpress directory. How do I move my install from the wordpress dir to my root dir? Does this help me in anyway? Would it be easier to install from scratch again but in the root?

Thanks
Jay