Now it is possible to help you with the information that you have provided.
A simply check of the Hotmail / MSN page from my machine sees a pic matching yours. Therefore I think we can conclude that this is the "normal" login page.
On the login screen changin it could be many things from hotmail upding it's service to your virus scanner clearing cookies making the page relaod itself from it's inital login page. Nothing to worry about as far as I can see.
No worries on trying to make your point. Just try to elaborate in future to save this happening again. We are all here to ask and help depending on the circumstances.