computer suddenly very slow. cpu usage <10%

My computer was running fine until yesterday. Today it takes over 20 mins to boot up and is too slow to use. I haven't really done anything out of the ordinary.
FYI windows 7 home premium 64bit
4GB RAM
Intel core 2 duo cpu t6600 @ 2.20GHz
Thanks

Maguscreed said:

First culprit in sudden slow down is generally malware.
They offer a free version of this tool and it's detection rate is very high.
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I haven't checked for malware yet because it's so painful to try and do anything with my computer right now. When it's a malware issue, isn't CPU usage very high? My computer right now is showing next to 0% usage, and I can move the mouse around just fine. It's when I try and actually do something that is the problem. I'm trying to reboot, but it's been about 15 minutes that I've been waiting.

I just ran verifier.exe and am trying to reboot. It keeps failing to reboot and trying to reboot again. It gets to the 'starting windows' screen with the glowing windows logo and then rebooting again. HDD issue?

now it wont boot up at all. it just goes to the 'starting windows' screen and then reboots itself. can't do a clean boot because i can't get to the start menu.

am i looking at a fried HDD? is there anyway to recover the data from the HDD?

i guess i'll have to wait until i have access to a computer with a CD drive. thanks for the help. i'll try this out and report back with news.

well, i can't even get it into safe mode boot now.
i push f8 when it's starting up, choose safe mode and then screen goes blank and fan hums along.

Work through these steps for Troubleshooting Windows 7 Failure to Boot