Vista - Windows Easy Transfer Wizard hangs at 34% calculating size needed

I am trying to use the Windows Easy Transfer Wizard to effectively back up my
son's settings, documents, and music onto another hard disk on the same Vista
computer.. as insurance in case we get a crash on the main harddisk. I used
Easy Transfer to get our accounts on this computer in first place, so I have
used it successfully many times before.

So.. I log in as him. I start Easy Transfer Wizard. I select this as my "Old
Computer", I chose to transfer to a disk, I chose "Only my accounts and
settings", and it goes to the window showing his folders with checkmarks. It
automatically starts calculating the size of the data to be transfered. It
gets to 34% and hangs everytime. Disk activity goes for awhile then also
stops. It can sit there for an hour. If I try to cancel it, it says "Not
Responding". If I look in Taskmanager migwiz.exe is using 50% of the CPU.
Finally I have to kill the migwiz.exe service in Taskmanager.

Any suggestions what next steps to take? He does have 16 gig of music, but
we move it all to this computer with Easy Transfer Wizard in the first place,
so I know it can handle it.

Anyway to "clean out" any migwiz settings or remembered values from the
various kills?