Hi, thanks for the response.
I did not intentionally reformat the drive. I put in the new OS disk, and then just clicked INSTALL as far as I know. If I saw an option for a clean install I would not have intentionally selected it, but I suppose it is possible that anything might have happened. I don't really recall any install options. After about an hour or so, it said "less than a minute left", then it locked up. The computer was frozen (could not even force quit), so I had to power it down. When it came back up, it was going through that animated "welcome" sequence with the cosmic background, that then started the sequence of pages asking me to make a new account.
I did back up the drive before I inserted the Snow Leopard disk, but I don't understand why I have to make a new account even if it reformatted. When I tried entering my old account info, I got a message saying that the name was already in use, so why don't I have an option of using my same old account?
Thanks again p.s.: I have been using Macs for 25 years and have done updates before and never had an issue.