Adding a password to your user account is easy. Follow the steps below to add
a password to your user account in Windows Vista, and have it prompt you for
that password at boot, and when the screensaver comes on...
Click on Start, then click on Control Panel. In control panel, click on
"User accounts and family safety" then click on "Change your windows
password" (Note if you don't have a password, it may say "Add a windows
password" or something similar) This will take you to the "User Accounts"
screen. Click on "Create password" or "Change your password" Enter your
password in the boxes shown (Note if you already have a password, you must
enter your original password for verification) enter a security
question/answer then click ok.
To have Windows prompt you for a password when the screen saver runs, Right
click your desktop background, and choose "Personalize" In the new window,
click on "Screen saver" Choose the desired screen saver from the drop down
menu, and set the amount of time you want Windows to wait, before activating
the screensaver. Make sure the box is checked that says "On resume, display
logon screen" Once you've done this, click ok, and close the window. (NOTE:
For password changes, you may need to restart your computer, or log off, and
back on for the changes to take effect)
In answer to your other question... The only way he can see what you're
doing is if he is an admin on YOUR computer. Network admins don't have
exclusive access to other computers without the use of external software that
would allow them to remotely access them. If they try to use your computer,
then they will need to know your password in order to gain access. If you do
not have a password set on your windows account, or computer, then anyone can
get on your computer, and look at everything when you're not there.