I stupidly put a screen saver on my computer which now I know is a virus as the screen turned black and stayed as such.I turned the computer off in desperation without shutting it down properly which was a daft thing to do I know. I tried booting it in safe mode without success as the screen just turned black again. I have purchased a windows 7 repair disc but as of yet not used it for the uncertainty of going down that route. Could I be advised please to the best course of action I should take next? I appreciate your time in this matter.