Disk Response Time in Windows 7 Resource Monitor?

I personally use Microsoft / Sysinternals Process Explorer.

Click on one of the four graphs at the top to bring up the current system information, then you can click on any of the peaks under the I/O bytes History graph and it will tell you what is doing the most hard drive related activities at any moment.

If however you are getting no peaks and very slow responses, it could be a sign that the hard drive is dying (or in some rare situations, faulty memory)

99% it's your hdd!

I have seen this problem on 3 Laptop running Windows 7 in the last 6 months.

Each time replacing the HDD has fixed it.