KP, yup this is an easy one although to some extent the file location varies with the version of windows you are using.
I did what you want to do when I upgraded from W98 to W2000. The single file is called:
mswkscal.wcd
and on Mrs fob's PC using W2000 it is in:
Program Files\Common Files\Microsoft Shared\Works Shared
Hers is only 240 KB because she doesn't use it as much as I would like! When you find yours you may find that a single floppy is all you need to BU.
Quick way to find it is to run a search on the name above. Or make small change to the calendar then quickly run a search on all files changed in the last day and sort by date/time.