Can WinXP SP2 be used with only an Administrator account?

I had a crash and did a full install of WinXP SP2.  I work alone at home, security is not an issue, hence, I usually set up the install without passwords for Administrator and for the 1 user I am forced to create, I entered Bernard.  I later run control userpasswords2 to make sure Windows goes straight to the desktop.

But in past installs, Windows has always chosen Bernard, the 1 user with Administrator privileges, to be the default user who is logged straight to the desktop.  Therefore, I was sure this was the case also this time and I proceeded with a full day of complex installs, settings etc.  To my dismay, I found out that I had done all the work while Administrator was logged in repeatedly by default, while Bernard remained in the primitive state as right after the install without icons, the default wallpaper and nothing.

1)  I would first like to understand what I must have done, so that in this install the Administrator account is not only suddenly visible, but became the auto-logon account in such a subtle fashion that I did not even notice it  please, answer that first, because without that full understanding, I am not sure that I have control over this for future installs.  Conversely, I may like for a strict development PC the structure of 1 Administrator and nothing else  but only if the file structure and the ramifications for finding and backing up all those files is the same as was always the case with the 1 user WinXP Pro forced you to create.

I tried a lot of things  I could not copy the profile from Administrator to Bernard, because the Copy To option was grayed out.

I worry about the file structure from all the reviews and posts I read:  The Control Panel  User Accounts applet is very primitive and does not even give me the option to delete the Bernard account, which has administrator privileges, even while I am logged on as Administrator.  Therefore, if I step this up and go into Computer Management  Local Users and Groups  Users  I am not sure from the horror stories what is true and what is not:  Will deleting the user Bernard even be permitted?  Or will WinXP Pro insist on leaving at least that one extra user?  And what will happen to the folder tree C:\Documents and Settings\Bernard\My Documents?  Where will all the critical files go, like MS Outlook 2003 Outlook.pst and all the MS Word files saved by default etc.?  Will they all simply be found in the Administrator Document folder tree, because I am now constantly logged on automatically as Administrator, i.e., in C:\Documents and Settings\Administrator\My Documents?

What should I do?  This is NOT a security issue for me  this is a secluded area in my house, where I work alone, all math and statistics, not of much interest to anyone.  This PC is behind an expensive router with built-in firewall and there is limited Internet browsing, there is solid CA anti-virus, SpySweeper with all shields, SpyWareBlaster, SpyBot, SecretMaker, WinPatrol Plus etc. etc., hence, security is NOT an issue here.

Please, focus on the folder structure and whether the pertinent files, especially Outlook, Word and Excel, will be just fine to use out of the Administrator folder structure.  If this is feasible, then how do I delete the 1 user Bernard safely so that its folder structure is deleted, too?  Please, note as mentioned above, that the User Accounts applet in Control Panel does NOT offer the delete option, meaning that I will have to step it up in order to delete that user  and that makes me worry about remnants of or leftover of the complete folder structure of a deleted user.

Can WinXP be run only with the Administrator and no other user?  I know that the Guest user and possible the ASP.net user may have to be left on the system from the MS knowledge base, but have to also report that strangely, in this install I also cannot find an ASP.net user in my new system.  All else works fine and it runs lightning fast.

Any help will be greatly appreciated.

Sincerely,
Bernard