"Advanced Analysis" check box grayed out

With Recode, if I revisit a DVD, it imports very quickly, and then has the “Advanced Analysis” check-box grayed out. It must store temporary files somewhere, but I can’t figure out where.

How do I get Recode to start fresh and not have the Advanced Analysis box grayed out?

For me, they are here:

C:\Documents and Settings\All Users\Application Data\Ahead\Nero Recode