I recently purchased leopard for my 2.16ghz 1gb(soon 4) 120 gb macbook. I am debating whether to go with the archive/install way or the erase/install way to upgrade. My macbook currently has 57gb of use. This computer is for college and will be used for the next 4 years. Also, which one uses up more of the computers memory? and how much of a difference would it be? basically i am asking for the pros and cons of each. thanks!