The standard installation image does come with mint4win, which used to be based on Wubi, the "Windows-based Ubuntu Installer", which provided a way to install an Ubuntu-based OSes toOS in a dual-boot machineconfiguration without having to muchmuck around with disk partitioning, and. It also gave you an easy way to uninstall using Windows' Add/Remove Programs feature. However, Wubi is no longer maintained. So if you run mint4win on a Windows machine (which I tested), all that will happen is it will ask you to reboot, and after that you have the usual choice to boot to OSGeoLive and install from there.
Thus, the Windows and Mac installers that come optionally with OSGeo-Live are not installers for OSGeo-Live, they are installers for Windows and Mac versions of many of the packages (QGIS, uGig, etc.) that are included with OSGeo-Live. As pointed out by @iant, using OSGeo4W is a better approach (for Windows, but not Mac).