Recently my new MB Pro (OS X, 5.6) began running significantly slower and taking longer to boot up. I deleted videos and apps that I don't use, but haven't seen any improvements. Please advise on any disk utility software that's out there. I'm new to the Mac world, so don't really know what to look for (my old PCs had the defrag and disk repair utilities preinstalled). I looked at the Leopard Cache Cleaner, but there are several bad reviews, so I want to get some feedback before buying. Thanks in advance.