Answer
There's no direct way to disable the Send Email option in the Print dialog itself. A workaround: create a catch-all Report Rule (leave the Report ID blank so it applies across all reports) with a 'Set Property' action that sets the Email property to a blank/space value — this effectively disables the Send Email To field in the Print dialog. Be aware of a real side effect: because a value (even a blank one) is technically present, the framework still attempts to send an email regardless, and that attempt will fail in the notification queue with an error like the 'To' field needing to be specified — generating one failed Application Message per print job as a result. To avoid the failed-message buildup, you can either route the rule's Email property to a dummy internal address instead of a blank space (so the send at least succeeds against something harmless), or accept the failures and periodically clean up failed messages from the notification queue.