Leopard - Clean Install or Upgrade?

[Nabooly]

i just got my MBP in June. I should probably just do an upgrade, right? And with an upgrade, Mac Office files and iTunes files/library and all that stuff remains intact, right? Im not going to lose any of it?

Nope, thats why its called an upgrade. Everything will still be there in the same place, and im almost positive that all your settings and preferences will stay the same.