Wss v2 is completely different than wss v3. Have to upgrade the farm from wss
v2 to v3.
Build a system (can be a laptop, desktop, vm, doesn't matter) as wss v2.
Export your site and import it into the new one, aka staging environment.
Upgrade it to wss v3. Test it to make sure it is fine (good idea, not
mandatory). Then export it from the new staging environment to the wss v3 one
you need it to be in. .
I've used vm's and desktop for my migration environments. With vm's you can
use the undo feature to revert back. With desktops, I ghost it to revert back.
This will save you from having to spend all the cycles in the future.