But before you start your download engines, here's a rough idea about file sizes of Windows Vista and Office 2007 installers:
Microsoft Office Ultimate 2007 - DVD (English) - 533 MB
Microsoft Office Professional 2007 (English) - 411 MB
Microsoft Office Professional Plus 2007 (English) - 467 MB
Windows Vista (x86) - CD (English) - 608 MB x5
Windows Vista (x86) - DVD (English) - 2555 MB
Windows Vista (x64) - DVD (English) - 3621 MB
Windows Marketplace workflow is quite similar to MSDN or TechNet subscriptions - once you buy a software, the license keys are immediately published on the Microsoft website.
The file transfer manager software will download the installation files for you in the background and will also resume any interrupted or broken downloads.
Thought the Office 2007 and Windows Vista installers are available as ISO image files, the download manager will also handle the software installation for you. You may no longer require the services of a local geek to install these ISO images for you.
When companies like FedEx and DHL can deliver shipments the next day, am not sure what percentage of users will use the Windows Marketplace to download such bulky software - they are not just big, you neither get the software manuals nor the innovative packaging.
Alternatively, if you have the Microsoft Office 2007 Trial CDs or DVDs, you can always convert the Office 2007 trial version to a full retail version without reinstalling the software. Once the software expires after the 60 day limit, get a product key from the Microsoft store and activate the software.
Related: Use Office 2003 to Read or Write Documents in Office 2007 Format