ATA HDD acts strange Windows 7

Hello, ever since i have installed windows 7, my ATA HDD started to act strange, every time, after some time, i access it it lags out the explorer and gives off a sound as if it was off line and just now got started, aka a spinning sound.

My main HDD is a SATA 640GB WD6400AAKS
On windows XP my ATA HDD worked perfectly, so i thought it was broken, i went and got my second ATA HDD, WD 800, it started giving the exact same issues as the other one.

This is what happens:

I click on my computer, open any partition of any HDD, explorer stops for a second, HDD gives off a sound as if it started spinning just now, gives of the sound of HDD needle moving, and than everything starts working fine.

Im guessing Windows 7 just turns off my HDD after some time of not usage. But im wondering is it a good idea to do this, on off on off, can this do damage to it?
Also i did put Maximum power usage in the power options, and this still happens.

Any answers/suggestions?

Go to control panel and choose “power options”.

Navigate to:

Change when the computer sleeps/Change advanced power settings

Look under “hard disk” in the window

Look under “turn off hard disk after”

What do you see there? If it is set to “never” and the drive still turns off, try “restore plan defaults”.

Ohh, so there it is! I remember on XP there were tabs, this is just hidden away >_<

Thanks, it was set t 20 min, I've set it to 0 (never), if this happens again, i will try restore to defaults.