This question may be answered several times already, but...

My laptop takes around 15 minutes to boot up. During boot up, the HDD light is permanently lit and I can hear the HDD whirring.
I can't do anything until the light goes out.
The IE7 takes another 5 minutes to open (although there are no problems once open & working).
I have run spyware killers, anti-virus, history/temp file cleaners and registry cleaners; I have run scandisk, disk clean-up and de-fragmenter; none of which makes any difference.
Can anyone suggest anything, please?
Thanks in advance.