Command Prompt, System Restore, and other Startup Settings at Boot w/o Boot Disk
You don't need a boot disk to get to the "Advanced Options" menu.
From the Windows login screen: hold down shift key while clicking on the power icon in lower right corner. Keep holding down shift key and click on restart.
If you select an option, such as "Command Prompt" the computer will reboot and load into a basic graphical interface with a command shell window open and no other windows menus.