In most of the cases you would want to set password for your login since you access the services from remote. but you want your vista to log you in without asking password. to make that work:

Start sphere, then enter "cmd" in the search box. In the Command Prompt window write "control userpasswords2" and hit enter.

Windows Vista will now ask you to elevate the privileges of the process so do it and you will be face to face with a window for User Accounts. Toward the top you will be able to see the option "users must enter a user name and password to use this computer." Select the account you wish to alter and then uncheck the option. You will then be prompted with an Automatically Log On window, in which you will have to enter your name and password.