There are several options you can try.
First, open rpmdrake as root, and click on the define sources button. Select the directory where you d/l your rpms and define it! next, deselect all the other sources, so that you only see the rpms you d/l listed.
select the ones you want to install and away you go.
If you get dependencies errors, install them in the following ways:
arts, arts devel
kde-libs, kde-libs devel
kde-base, kde-base devel
and the rest dont matter.
Or you could use console and try
su
<enter root pwd>
urpmi *
hope it works