I have an old PowerBook G4/TiBook 1Ghz and want to erase everything on the drive to start over with a newer operating system (it is currently running on 10.3.9). What is latest OS that can run on this old baby and how do I erase everything and start from scratch? I'm an idiot when it comes to this kindda stuff! Thanks! 
Here's the Hardware Overview:
Machine Model: PowerBook G4 15"
CPU Type: PowerPC G4 (3.3)
Number Of CPUs: 1
CPU Speed: 1 GHz
L2 Cache (per CPU): 256 KB
L3 Cache (per CPU): 1 MB
Memory: 512 MB
Bus Speed: 133 MHz
Boot ROM Version: 4.5.3f2
Here's the Hardware Overview:
Machine Model: PowerBook G4 15"
CPU Type: PowerPC G4 (3.3)
Number Of CPUs: 1
CPU Speed: 1 GHz
L2 Cache (per CPU): 256 KB
L3 Cache (per CPU): 1 MB
Memory: 512 MB
Bus Speed: 133 MHz
Boot ROM Version: 4.5.3f2