I have a MBP with a 2.4 ghz SR cpu/4 gb ram and a 160 gb 7200rpm hard drive that I bought about 14 months ago and it came with Tiger and now runs 10.4.11 I would like to install Leopard but I am wondering if doing so will hurt its performance in any way? Is it good enough to run Leopard as well or perhaps better than Tiger? If I install, should I do a clean install and reinstall all of my apps as well? I definitely do not want any problems caused by just installing over the current setup. Also, besides my personal files, how do you back up the mail settings and emails, the internet settings and the address book? Thanks a lot for any advice.