Anne, you cannot use URL directly, use examples like www.mydomain.com/blog, else your post will be deleted.
and I am having really hard time believing that you actually kept WordPress which is actually a BLOG script on main and keeping Moodle which is LMS on BLOG sub-domain, making me believe you actually haven't done ANYTHING regarding learning about what Moodle is. You'll be better off extending your current WordPress based site to be used as client training on your product, not that I want to push you away from Moodle, but what your goals are, Moode is not the product of choice.
If you believe that training is integral part of your business, then build your site around Moodle as all the static pages you have currently on, can be built within moodle as well.