This guide was done in OS X 10.7.2 Lion with the newest version of VirtualBox, it should work to install OS X in Windows too.
- Open VirtualBox and create a new Virtual Machine – make the virtual disk at least 15GB and allocate at least 1GB of RAM to the VM
- Choose “Mac OS X” and “Mac OS X Server” as the OS and OS Type
- Select the Snow Leopard DVD, DMG, or ISO as the primary boot drive
- Confirm the specs, boot disk of and choose “Create”
- Now boot the newly created VM by clicking on “Start” and let the Snow Leopard installer load, click through to the “Install Mac OS X” screen
- Pull down the “Utilities” menu and select “Disk Utility” – this next step is important because without it the virtual drive will not appear in the install menu
- Select the name of the virtual hard drive on the left side menu of Disk Utility (15GB VBOX HARDDRIVE or something similar) and then click on the “Erase” tab
- Choose “Mac OS X Extended (Journaled)” and name the hard drive something, then click on “Erase”
- Now quit out of Disk Utility to go back to the general Mac OS X Installer
- Select the hard drive name you just formatted and click on “Install”
- Let the installer run, this will take a while (30-45 minutes) and just ignore the “Time Remaining” estimate because it’s inaccurate – if it looks frozen or stuck, it’s not, the progress bar just jumps in huge chunks rather than gradual increases
- After the installation is done and you’re back at the VirtualBox Manager screen, click on on the gear icon for “Settings”
- In Settings, click on “Storage” and then look under “IDE Controller” to remove the Snow Leopard install DVD, ISO, or DMG – if you don’t do this, the VM will boot back into the installer rather than into Mac OS X 10.6
- Close out of Settings, select your VM, and click on “Start” to boot the virtual machine
If you see a bunch of error messages with white text on a black screen, ignore all of that and let VirtualBox boot. Soon the familiar Mac OS X Snow Leopard setup screen will load to pick region settings and setup the virtual machine as any other new Mac. Enjoy!