Windows 7 Blue Screen of Death

Hi, I have windows 7 Ultimate and my problem is that while booting my windows boots till the login page ,but i cannot find any login box to enter password and no icons to restart or perform any kind of function,the function ALT-CTRL-DEL is useless,i can just see is "Windows 7 Ultimate" written on the bottom of my screen and nothing else with blue windows background.My keyboard is useless at that...