El Grifo, the "Main Mission" was a host of scientific experiments - a Space Laboratory, if you like. A wealth of info is avaiable on the
STS-107 site at NASA. This is on the
Missions site which has details of previous & future flights. Further exploration of the NASA site will answer most of the other foregoing questions (or FAQs!) on the subject.
Due to the fact that there has suddenly been an uncharacteristic surge in space-interest from the press and public, no doubt some sites are a bit slow right now.
There is also an excelent and very up-to-date site at
Space.com, and many others. Hope this helps.