I am having problem wit computer that will require putting in new drive and rebuilding with new operating system I have Photoshop CS6 and Lightroom 4 both installed on this computer and laptop. Anything I need to do prior to reformating drive and rebuilding. I have serial numbers for both programs.
Assuming you can still run Photoshop, it would be a good idea to go into its Help menu and choose Deactivate before taking the system offline for its final time. Then you'll be assured of being able to reactivate on the other side.
I don't know if Lightroom works the same way, but if it does the menus will likely be similar.