Automatic selection of user account at welcome screen of W..

Good day,

I realize this isn't a major issue but I don't like when things have changed
on my computer that I haven't requested. Basically after installing the .NET
framework update that came down (and having to reinstall IIS in the process
to get that to work), I find that at the welcome screen I no longer have to
click my user account to get the password entry box to appear, it's done
automatically. I am running Windows XP Professional SP3. I've spent a lot of
hours trying to find a setting that would cause this. I am not sure if it is
related but the defaultuser in the winlogin section of the registry is always
being populated when I logoff/restart. I am also the only account that shows
up, but that never mattered before this last update. I tried deleting that
but it keeps coming back. Part of the problem is the "problem" occurs at
start up before I'm logged in to run anything to see what is happening.
Anyone have any pointers or thoughts of what I can look for to keep working
on this?

(May be some typos/errors in what I am mentioning here)
I've researched policy's and groups and tried lots of combinations of things
in there
I've tried messing around with the winlogin part of the registry
I've tried control usrpassword2 settings
I've tried lusrmgr settings

Please don't waste anyone's time flaming, cause unless you know everything,
there is something you don't know too. And I'm thinking of a number, do you
know what it is?