Black screen after logging in

Hello,

i know there are many threads already about this, but i dont understand them well, as my knowledge about computers is very limited (VERY limited). So, today i wanted to use bluetooth, but it didn't work. The last time i tried using it was probably about a month ago, and it worked fine. Then a week ago, my computer started installing windows updates when i turned it off, but it got stuck at 4/6. So i found a solution online and did something, somehow, i think i disabled automatic updates. So today, i really needed the bluetooth to work, so i again started searching for solutions. After nothing had worked, i decided to recover my system to about a month ago, even before the windows updates (if this is important anyway). So the system recovers, i type in my password, but the screen was just black, there was only a mouse coursor and i could press ctrl+alt+del. Then i went to safe mode and it asked me if im happy with the recovery or whether i want it to go back to the state just before the recovery. And because of the black screen i wasnt happy, so i said yes, please go back to 6.2. Well, the screen is still black after i log in :S I really need my computer but i don't know which solution to choose, because there are so many. Besides, i dont understand almost any of them. I could also format it, but i'd need a cd with windows, right? Any help would be appreciated. Thank you!