Hmmm...
this page
http://docs.info.apple.com/article.html?artnum=301270
says
"Archive and Install installations require the greatest amount of available disk space because you need to have room for your existing System and the new one you are installing."
I don't have enough space.
So is the best way in this case to delete my huge /Users folder and copy it back after the install?
What if I chose the 1st option, "Upgrade", that apparently doesnt duplicate the whole system. Dont know if I'll have that choice until testing later...
I'll tell you, what I typically do with problems, before buying Superduper, is ditto my /Users folder to a 2nd HD, then wipe the boot drive clean and do a fresh install. Then in SysPrefs>Accounts I add back all the different Users I had, being very careful to always add them in the same order as I did the 1st time so they get the same UID as previously. Then I carefully swap the fresh /Users folder for my old large /Users folder, usually in single user mode when Im being careful.
Which way do you think is the fastest/best?