Can I swap out Office 2010 Home with Office 2010 Professional?

I have two laptops each with a copy of Office 2010. One is Home & Business and the other is Professional.

I need to have Publisher, which is part of the Professional package on the laptop that has the home version. I do not want to lose my mail and files. Is there a way to load from the DVD without uninstalling.

I have both discs and both keys. I just need to flip flop versions without losing anything on each machince.