I'm thinking I may want to downgrade back to Leopard from Snow Leopard. I continue to get the 20-second "beach ball of death", maybe once or twice a day. It's really annoying me. Can I reformat/reinstall Leopard on my MacBook Pro and then restore my user data from Time Machine? Or will that cause problems since my Time Machine backup is from a newer version of OSX than what it will be restoring to?