When I turned on my computer this afternoon, XP was booting noticeably slower than normal. When I got to my desktop, I was getting mouse lag and my CPU usage was at 50-90%. When I tried to reboot, it took forever and finally told me that a regristry file was corrupt or missing. I ran the setup disk to get to the repair console like it told me to, but it doesn't give any further directions. What do I do?