Deactivating <Ctrl>+<Alt>+<Delete> to Start Logon
Access to Windows Classic logon window usually is initiated by pressing together the keys <Ctrl>+<Alt>+<Delete>
Forces the XP security logon sequence
However requirement can be disabled
Edit with Local Security Policy dialog in "Administrative Tools" (Security Options):
Interactive logon: Do not require Ctrl+Alt+Delete set to "Enabled"