I have read that defraging is not nessesary on a MBP unless you have large files (which i don't). But, is there anyway to do a "clean up"/remove unnessary files or remove a file completely after being deleted? I searched on apple.com/support but have a question on what came up (will this help to free up / fully remove files that have already been deleted?) http://docs.info.apple.com/article.html?path=DiskUtility/10.5/en/duh1010.html . Does this fully delete things that i have downloaded, but then erased, that may stay on the HD? or will this completely delete the HD and/or files that i need?