Diblo

Install the vista!.

Add a none admin user for you self and for all other.
Put a password on the admin account.
Log out and in on your new user account (none admin)

When you need admin rights there will come a box where you have to type the admin password.
This box will probably normal be see if you add and remove programs, and some other thinks like control of user accounts.
It is normal if you have install a program you have the rights to run it.
The message that you need admin rights will be reduced a lot.

Only thing you have to remember:

1. This box will give access to the admin account.
2. The box will not come by self. if it do scan you computer.
3. If you account is dame you have to reboot and login as admin and add a new user account.

Think you about before you type the admin password.

This will give you a much more user friendly and secure computer.