Hi Guru Steve,
First off, if you do upgrade to Office 2007, you will still be able to view older documents from Word and Excel. Word can also be left in the .doc/.dot format if you prefer, but you'll have to do it from the options menu, if you decide to get Office 2007. And yes, Office 2007 works under Windows 7, both 32 & 64-bit. I'm currently using Office Enterprise 2007 on Windows 7 Ultimate x64 without any issues.
As to your first question, as to whether you can use Office 2002 on Windows 7, well have a look here Windows 7 Compatibility Center search results - word 2002
but be aware the search doesn't bring up "Word 2002" search so...???
Hope I've helped a little.