Computer won't work in normal mode

I took the battery out of my laptop and just ran it on AC power but when it was in the middle of shutting down, I forgot the battery wasn't in the laptop and unplugged it from the power supply. The next time I went to use it I got as far as the black loading screen for vista. So I tried it in safe mode and it worked, so I tried a recovery and that seemed to work because I was able to log in but after a couple of seconds it would freeze. Sometimes I don't even get as far as this because when I click on my user at the login screen instead of telling me to enter my password, it just goes blank. Ideas? Summary - works in safe mode but not normal mode Also, I'm considering just copying all my files onto an external hard drive and just restarting the OS or whatever I have to do. Is this a viable option and if so how should I go about doing this? Thanks