No Admin Account Active

I have a problem and I need to avoid having to format the pc, so I hope someone can help me.
I was playing around with the settings and changed my account type to user thinking its safer, then I got tired of having to choose the user account on startup every time so I logged in as Admin and disabled Admin account in (Manage), the problem now is that there is no Admin account active and I can't seem to enable it again being a standard user. Even running things as admin doesn't prompt for password.
I know the Admin password but I can login as Admin because its disabled, so now what?

Try opening a command prompt with admin then type net user administrator /active:Yes

Ok, I have the problem half-fixed, I booted in safe mood and logged in as built-in Administrator, which shocked me because all of this security is useless if you can do that!
Now I enabled the Admin account with the admin rights that I made and I can access it again, but when I login as user and I try running something as Admin I get error message about privilege bla bla bla but no password prompt as it should be so you can run as admin, whats the deal?

Ok, all is figured out, now a winows prompt for Admin password when needing Admin rights to do something or when I try to run something as Admin, maybe it had to do with UAC?! no idea
I also followed the instructions on this link Automatic Logon Into Windows 7 | Windows 7 News
So I avoid users boot screen.
I still wonder why there is built in Admin account, anyone can boot in safe mood and do whatever