Hi Bob,
Generally the hyperlink in the task form is just a reminder for the task owner. I am not sure why you need to submit the InfoPath form from a task form. Basically the InfoPath form should have been submitted before the task created. Anyway, as a workaround to avoid this issue, I suggest you click the link by pressing the Shift button at the same time. By doing this, the InfoPath form will be opened in a new window. Besides, changing the task form from a dialog to the full page in the List Advanced Settings should be able to avoid this issue as well.
Thanks,
Reken Liu