My computer will not go to the logon screen

I thought that I could fix my HP dv6700 computer when one side of the computer came completely apart (top separated from the bottom) well I took the computer apart, and it just turned out to be one of the screws had fallen out, luckily I was able to tighten the piece back inot place, but when I put everything back together the display was not working. It flashed the HP logo and that was all, so I took it apart again and finally discovered that it was a cord that had come undone, and I plugged it back in and it finally displayed that screen that says some problems occured while starting your computer, and there were two options to click, start windows normally or scan windows for problems. I have done both of those options now, and all that my computer will do is act like it is going to the logon screen (on the bottom of the screen it says copyright Microsoft Corporation with the scrolling indicator that something is loading) but it goes no farther than that. No matter how much time I give it, and I have already tryed removing the battery and checking the charge and none of that helps.