Windows 7: Remote Desktop and VNC login issues

I am running 7 Pro. I have no problems logging into my computer from Internet and work using either VNC or Remote Desktop. My issue is that with UltraVNC I have to enter my user name and password BEFORE I get to the password on the desktop which is great BUT the speed stinks.
Using Remote Desktop I go straight to the locked desktop screen and it asks only for my desktop password.
No good when u want the security in case someone from work uses your computer while u are away. I know I can lock the desktop at work BUT that is not an option due to my work enviroment and this e=being a shared computer.
This way if I walk away and someone clicks on the VNC icon they have to guess my login name and password. With Remote Desktop they see my home compter screen right away and all the have to do is put in password.
So it there and way that Remote Desktop from Windows 7 will ask for a login and password all the time and NOT remember its last session logins?