Do you intend to use Office to make money? If so, the Student Edition is not for you.
I have a friend currently using some version of Office Enterprise and it contains: Access, Communicator, Excel, Groove, Infopath, Onenote, Outlook, Powerpoint, Publisher and Word. I did not know what the heck Groove is/was, so I guess I do not need it.
There are tool bars in Word that let you use features of other programs the Student Edition does not include. MS seems to be all about tight integration.
I do not know the differences between individual Office components, but I am guessing the differences are either very minor or there are none. I tried my friends version of Word and I did not notice any differences, but I did not explore Word in depth.
One very BIG potential issue is the licensing differences between Student Editions and the rest. From the MS Site:
"Office Home and Student 2010 is licensed only for non-commercial use by households. It cannot be used for any commercial, nonprofit, or revenue-generating activities, by schools or academic institutions, or by any government organization."
So you cannot sell that amazing novel you wrote using the Student Edition but you can if you use a different version. I do not think MS really knows, but they might, so write under the cover of darkness and keep your mouth shut.