in reply to
Migrating mod_perl, perl, apache and mysql to windows 7 64bit
This is not relay a perl question.
Short answer: It will probably work. You can run 32 bit binaries on 64 bit windows, and I can't think of any other reason why it won't work.
Long answer: You need to do some testing before the cut over, so that you have time to fix any problems that arise. We don't know the details of your mod_perl application or your environment, so we can't guess if it will Work OK in a different environment.