what must I do to retain all the saved PSD/PSB files that occupy my HD in the event that they are to be printed at a later date?
Not much. Lightroom will continue to work, so you will be able to print or output the PSDs, and adjust them to some extent. The PSB files are more of a problem. They can only be opened in PS so you would need to export JPEGs or flattened TIFs/PSDs while PS is still available.
I think that I failed to explain my motivations...want my children to have the ability to view and/or print my images at a later date. Kind of an inheritance thingy. What do I gotta do?