I saw something in the Microsoft Windows 8 presentation where instead of entering a password, a PC could also be unlocked via a picture by clicking on some user defined positions. Is this available on Microsoft Surface and if so, how can I enable it?
Yes it is available on the Surface:
From the start screen, swipe in from the right to bring up the charms bar.
Select "Settings", and then "Change PC Settings".
Open the "Users" section, and under the "Your account" section on the right hand side there's a section marked "Sign-in options".
You should see "Change your password", "Create picture password" and "Create a PIN".
If you've set up the mail application to talk to a corporate Exchange server, it's possible that the security settings enforced by that will block you from setting some of these features up - especially the Picture Password as it's considered "less secure".