Originally Posted by Tauron
Neither: mail, calendar and address book is all you need and 100x better than those programs.
You'll be right. But not right now. Right now, if the requirement is Outlook compatibility, Parallels or VMware is the best option - if you want to stay within the confines of the Mac experience. Otherwise Bootcamp.
When Snow Leopard is released, this *probable* solve all your Outlook problems because then you can simple natively use OS X's built-in Mail, Calendar, and Address Book to manage your Exchange (Outlook) profiles. Without the choice between crappy Entourage or worse Outlook. Snow Leopard is planning on being released in September ( I think - might need to check the date on that ).
***Resist urges to go off on super hostile angry rant on Outlook, Entourage, and Exchange....
*( If it is an option, see if you can migrate your dad off Exchange dependence, if possible).