Ideally this should be done on a clean hard drive when installing the operating system.
I live quite happily with just one partition on my hard drive.I just back up externally important documents just in case though
It depends on what you plan to do with your harddrive. If you plan to dual-boot with Linux then most distros come with G-Parted but otherwise youd need something like Partition Magic which isnt free and the trial version, I think is not fully functional.