I'm really liking Time Machine. Maybe it's the novelty of it and perhaps it will wear off soon. However, one thing that kind of bugged me was there didn't seem to be a way to tell it WHEN to do a backup. In other words it starts pretty much after you turn it on and then each hour after that. However, there were a couple of times I didn't want to wait until the next hour and I wanted to start it immediately.

There is a way:
Hold down your mouse on the Time Machine icon on the Dock to popup the menu.
Choose "Backup Now" and Time Machine will start the backup immediately.

Is there other settings in Time Machine Prefs?

Just the ability to choose the drive, turn it on/off and what NOT to backup.