The Remote Service Installer is for users who install SmarterStats Enterprise Edition and wish to distribute their installation between multiple servers on their network.
For more information, see the SmarterStats help topic Installation - Installing the Remote Service.
SmarterStats Free offers complete business and web analytics for a single website. It includes all the features of SmarterStats Enterprise except for use of the distributed reporting service, so you're limited to analysis of one website.
The Free Edition is primarily used to give you an opportunity to try out SmarterStats before making a purchase decision. However, small companies can use it as a free, full-service web log analytics solution.
Use the instructions on the Current Build tab to download SmarterStats. During the installation process simply select "Free Edition" when asked to provide a license key.
Below are links to some articles in the SmarterStats Help documentation. These articles are good for gathering information such as the system requirements for SmarterStats, edition explanations, deployment guides and much more.