To help determine which version would meet your needs, Ed Bott created a table of features found exclusively in Windows 7 Professional or Ultimate. The purpose of the comparison is to provide a side-by-side showing of unique features in the Windows 7 Professional and Ultimate editions. If you do not need the unique features, it could well be that the Windows 7 Home Premium may best suit you.
Ed provides a detailed discussion of what the items from his table below mean on page 2 of Do you need more than Windows 7 Home Premium?
Still uncertain? Head over to Ed's detailed description in From Starter to Ultimate: What's really in each Windows 7 Edition?
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