The Oracle Solaris OS distribution you choose depends on how you want to use the system.
Use the Oracle Solaris 10 OS for mission critical activities and production, such as in a large enterprise.
For information about the Oracle Solaris 10 OS, see the Oracle Solaris product site.
To get the Oracle Solaris 10 OS, see Get It: Oracle Solaris 10. You can download the Oracle Solaris 10 OS, you can download the Oracle Solaris 10 appliance image for VirtualBox, or you can order a DVD media kit. You can also get information about Oracle Premier Support for Operating Systems.
Download the OpenSolaris OS in a slim install configuration that fits on a single CD. Install the base OS from the CD, and then install additional software packages of your choice from the OpenSolaris package repository. Alternatively, use Automated Installer to install the OpenSolaris OS and your complete working environment on multiple machines.
For more information about the OpenSolaris OS, or to get the OpenSolaris OS, see the OpenSolaris product site. You can download the LiveCD image, you can download the Automated Installer bootable image, or you can order media. You can also download VirtualBox.
For information about Automated Installer, see OpenSolaris 2010.05 Automated Installer Guide and Migrating From Solaris Custom JumpStart to OpenSolaris Automated Installer.