Well, I don't think you can get exactly what you're looking for but check out the Login Options in the Accounts panel of System Preferences. You will want the "Automatically log in as" unchecked. You can then display the login window as 1) List of users or 2) Name and password. If you choose the first, a list of users with icons will be presented and once you pick one, you will be prompted for a password. If you choose the latter, you must type in the username and password. This doesn't get you exactly what you want but may be close enough.