If you have Vista certified machines and you are looking to upgrade to Windows 7 under the Open Charity program, then this is what you would need
With Windows 7 Professional, fewer walls stand between you and your success. You can run many Windows XP productivity programs in Windows XP Mode and recover data easily with automatic backups to your home or business network. You can also connect to
PcMall Part #: 7916125 Mfr. Part #: FQC-02322
If you want to do a clean install of Windows 7 Pro, Win 7 Enterprise, or any other version of Microsoft’s OS, you would use this sku under the Open Charity program which comes with Software Assurance
Microsoft Windows is an operational system for PC compatible computers with multi-task support and intuitive graphic user's interface. It has modest resource requirements compared to the more advanced operational systems from the Microsoft Windows family.
PcMall Part #: 7916114 Mfr. Part #: FQC-02323
With both of those skus, if you needed the media as opposed to downloading you would order the media direct from Microsoft.