To upgrade from a home version will require a Full license or a retail upgrade license. Neither is available from Tech Soup.
store.microsoft.com/microsoft/Windows-7-Professional-Upgrade/product/8BB1A4B4
Understand the upgrade process for your PC
Moving to Windows 7 Professional from Windows Vista Business qualifies as an upgrade. All other paths, including a move from a 64-bit edition of Windows Vista to a 32-bit edition of Windows 7, require a more detailed re-installation process.
From the store site it sounds like you may be doing a full install. It is alwasy better to start from scratch, then you know you are starting out clean.
Dave