Oh yeah, thanks for info On Svchost... actually found the skinny on it at about 4 am on another site... Vista uses it instead of exe files to run multiple apps if I got it right, so if one locks all don't go down?
No. It hosts services. svchost hosts Out-of-process services; dllhost hosts in-process services (dlls).
regarding your sudden user issue- in order to create administrator accounts you need administrator access; but from the looks of the error it isn't complaing that you already have an administrator enabled account but rather that the name you chose exists. Not all accounts display on the log-in screen. For example, the only account that I can see in most places is my normal account, "BC_Programming". However, when I visit Computer management's user section (start, compmgmt.msc,"Local Users And Groups","users" I can see:
__vmware_user__
Administrator
BC_Programming
Guest
VUSR_TERATRON
each one has a description- for example it reveals that VUSR_TERATRON is used by Visual Studio 2008.
Within this particular Dialog (computer management) you can investigate each of these users, as well. For example, my BC_Programming account is in fact more powerful then the Administrator account, as I've given myself Debug access. (for my programming needs).
Personally, I always use this particular feature to manage users; the default user account management is to limited for my tastes.
Regarding your problem- the administrator account is disabled by default- by enabling it (I assume) it should then display on the log-in screen, so, if for some reason your normal account no longer has administrator privileges, you should be able to log-in as Administrator and use computer management to make your normal account a member of the administrators group.
It's also possible the behaviour your witnessing is a result of UAC; when you log-in, your account is Always stripped of any administrator rights- windows takes your user security token and masks out the administrator privileges. When administrator access is required, the UAC prompt is shown before performing the operation with your full security token. I'm not sure how this works when UAC is disabled, but it might simply not show the UAC prompt and instead automatically perform the operation using the full security token. If that is the case, your normal user account will, while having administrator privileges, the security token used to start most programs will not, unless you use "run as administrator". On that note, the "Run as administrator" was exactly what you needed for that IE repair script; even with UAC disabled, you need to use "Run as administrator" to run the program with your full security token, rather then the normal one with the admin privileges stripped out.
re: your IE8 issues, try some of the steps here:
http://www.mydigitallife.info/2008/03/07/how-to-uninstall-windows-internet-explorer-8-ie8-in-vista/