The latest stable release of OSGeo-Live 9.5 :
osgeo-live-9.5-i386.iso : 3.9 GB
osgeo-live-9.5-amd64.iso : 3.9 GB
A Lubuntu based bootable DVD. It can also be copied to an 8 GB bootable USB thumb drive. Verify your download with its md5sum checksum (osgeo-live-9.5-i386.iso.md5) or (osgeo-live-9.5-amd64.iso.md5).
osgeo-live-vm-9.5.7z : 3.1 GB
Premade 7-Zip compressed virtual disk (.vmdk) suitable for use in VirtualBox, VMWare, KVM and other virtual machine applications. Verify your download with its md5sum checksum (osgeo-live-vm-9.5.7z.md5).
For a full list of versions, download options and mirrors visit: http://download.osgeo.org/livedvd
[*] Minimum suggested system resources: 768MB RAM (2 GB are better for trying Java based applications), 1GHz i386 or amd64 compatible CPU. No hard drive required. Mac users will benefit from a 3-button USB mouse. For installation onto a USB stick an 8 GB thumb drive is recommended.