Are you sure you formatted the previous OS partition? It would most likely have been the System partition, unless your boot files are on another partition as can sometimes happen on factory installs.
Have you made your Recovery Disks so you can wipe the Recovery partition? It will often not run anyway once you install another OS, and will certainly lose its links to Windows.
What does the partition marked System say it is for? Can you post back a camera snap of free Partition Wizard bootable CD drive map? Free Download Magic Partition Manager Software - Partition Wizard Online
If you had previous infection or other corruption, I'd wipe the target partition PW CD as formatting doesn't erase or overwrite anything. To get the cleanest possible install, I'd wipe the entire HD from the PW Disk tab, unless you need the Recov partition to possibly return to factory condition - you can also always order the disks or reinstall old OS using a retail installer with Product Key on COA sticker.