It seem you do all the checks, such as; Full format, Zero format, Surface test.
Hence, this is where you problem lies.
This way may even destroy certain sectors of the HDD.
By doing this, it mean that you are using old HDD, which was not stable before.
Surface test is a simply test, and not able to do a write test mode.
Your write test mode is by doing the zero format.
Booting will also depend on the HDD condition.
Hence, your Windows 7 slow down due to the all the test you had done.
Why don't you try to use Disk Defragmenter
Location: Start -> Accessories -> System Tool.
Select the partition/drive and do a "Analyze disk".
If this result is not favorably, this is no good.
As most the result is less than 5%.
On whether you want to do it or not, it is up to you.
Depend on this result, than we can move to next.
