I installed the windows vista service pack 2

I installed the windows vista service pack 2 update yesterday and late lastnight my computer froze so i had to use the power button to shut it off, the screen is blank and the led lights come on and you can hear the fan running but nothing ever happens i took the battery out lastnight and put it back in this morning and my screen came on and went to the start windows normally or launch startup repair which was recommened so i choose it and then i had large blue and white diagnol stripes across the screen and now its back to just the lights and fan running.