It's not logging you off, it's going to screen saver and the screen saver has
a password. In Windows 2000/XP, Microsoft began using the log on screen as
the same screen to dismiss a password proected screen saver. This provides a
more consistant experience, a more secure "unlock" environment, and of course
to make it more consistant and familiar so users see the same screen any time
the computer is locked.
If it "logged you off" it would close all your programs, and when you logged
back on, it would be like you had rebooted.
If you don't have a Windows password, you'd simply have to click OK at the
password prompt (Windows 2000/XP on a domain) or click your user name (if
using the Welcome screen with XP).
To disable this, turn off the "password protect" option on the screen saver
tab of display properties. This option will be labled "On resume, show the
welcome screen" if you have the welcome screen enabled AND there is more than
1 user account that would be listed on the welcome screen.
- skeene