migrated 7 wss 2 sites to wss 3.
I had to create the sites in Central Administration, then select them in the explorer-ish interface to migrate. There were good options to change domain names, and remove dead accounts.
My sites were small, but not all content was migrated. often had to do it several times.
turns out the Move, is just a copy, and move and delete old site, is just a copy and doesnt delete much. (Thank god.) If it had deleted what it didnt bother to copy over would have been a real problem.