I have a Macbook and I had Windows Vista running through Boot Camp and I deleted the partition and when I try to reinstall it it tells me that it can't partition the HD because there are some files that can't be moved. I have read on other threads that you can use iDefrag and do it that way, but I can't get that to work. The other option is to reinstall OSX which is Snow Leopard. My question is I don't have a way of backing up what I have now, so when I go to reinstall it will it erase everything on my macbook or will it leave all my personal info and settings the way it did when I upgraded to snow Leopard and installed it the first time. If so how should I do it, should I boot from the disk or run the disk when I'm already logged onto OSX? Please help me with this, any help will be greatly appreciated. Thanks.