Running Mavericks. Need to return to Snow Leopard
First I backed everything up on time machine, and I made a manual backup of photos, music, downloads, and documents to another HDD.

Next I put in the install disk from OSX Leopard 10.5.. Mavericks will let you enter the install process right from the desktop on Leopard 10.5, but nothing past 10.5. (If you don't have leopard you can probably get one off ebay, or find it on the internet somewhere.

The computer will restart into installation mode from which I erased the HDD. Then I installed 10.5 Leopard.

After the Leopard install you can upgrade to any version you want to. I used snow leopard because it only uses 1 gig of RAM.

My computer runs much faster again, like when I bought it. Sure there are some apps that don't work, but I have everything I need here.