Move directory of installed WordPress

Hello,

I am trying WordPress and I’m very happy with it. In order to test it and not damage my current site, I installed it on dedicate folder called WORDPRESS.

When I will be done with setting everything up, I would like it to replace my current site (which is only basic HTML pages).

How should I do it?
Should I move the folder content of WordPress to my root? If yes, in there anything I need to change?

I’m using Yahoo Small Business has host but I did an install of WordPress myself without going through the WordPress from Yahoo.

Thank you for your help,
Yael