All, this is developing into a great thread. OppressedC, thanks for your original request. Great installation-options information here that I haven't seen elsewhere (I'll have to perform more searches...)
So, correct me if this summary is mistaken: It is possible to preserve /home (as well as /usr/src, /usr/local, and /var/local) on the same logical partition as /, simply by unchecking the Format Partition option when installing Ubuntu OVER an existing installation. If, so that's EXCITING! -- Linux installation has caught up to Windows. In fact, that's been the only complaint I'd ever had about Ubuntu. I'm sorry I missed it in my Lucid re-install, and I'll be looking forward to taking advantage of it with my next desktop system.