Given so little details I can only write you should learn to use a LiveCD such as Ubuntu (see google) to get your files out. Read http://tips.oncomputers.info/archives2004/0401/2004-Jan-11.htm to see how we began doing that years ago. Today this is even easier.
Since we don't know which Vista DVD you have any advice is nothing more than a guess you could do that. For example once your files are safe and if it's like the Dells we have you can perform a "Vista Repair Install" (see google.)
Good luck,
Bob
I have a dell studio 1535, and recently my update file i think has corrupted itself. My laptop when it turns on attempts to update, but always will fail and re-start this. The update is forever stuck on stage 3 of 3 0% and it starts there aswell and just fails and restarts. I've tryed safe mode and such but it's not helped...

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