It would be great if the Autonumbering Wizard would support the discnumber. It already supports several directories with the "Reset counter ..." option.
So, two extra options would be great:
[ ] Set Discnumber tag (each directory contains one disc)
[ ] Save total number of discs in tag (total: 2) (or whatever)
or something along those lines.
If someone has a script for this, that would be great, too.
(I always number tracks and then discs, even if it is only one disc).