I just installed a HP printer scanner. Now, whenever I start up the computer, instead of going to desktop, it goes to a Microsoft screen saying: To begin, click your user name
The (my name) 55 unread messages
5 programs running
Turn off your computer
After you log on, you can add or change accounts. Just go to control panel, check user accounts.

Obviously your PC used to log into an account automatically but something's changed this. Try following the steps on here:

http://8help.osu.edu/2063.html