You can check here about system requirements for Desktop software:
BlackBerry - BlackBerry Desktop Software - BlackBerry Software at BlackBerry.com
Device software:
BlackBerry - BlackBerry Device Software
Not the exact links, but should be able to find what you need by looking around.
I'm sure RIM is in the process of making their software compatible with Windows 7. A few people have posted here about using Windows 7 -- can find the threads with a search.