|Hi, Thank You for all your help and advice, very much appreciated. I apologise for the lack of info on my part.|
It turned out that the hard drive had malware on it, thats the reason it was not letting it boot up properly.
The original hard drive already came with an operating system installed and ready to use. I initially restored it to factory settings using recovery partition. I installed an Antivirus and office programs. I thought this was a clean install, viruses/malware free.
It worked alright in the beginning (for a couple of weeks), I could use the programs I installed and surf the internet no problem But then I did not use it for a month. After this time when I switched it on it would not boot to windows. It switched on fine, it could go to bios no problem, but it just hanged at the windows 7 loading bar. One time I left it on for a couple of hours and it managed to reach the final black screen with the cursor/arrow key showing before displaying the desktop, and again hanged there for ages, never showed the desktop.
So I used my other hard drive (and memory), formatted, installed windows7, same thing again. I dont know how this second drive could have got infected. I did not buy any extra parts, I already had them as spare. I wouldn't buy any parts unless I was 100% sure they were faulty.
After taking T-R-A suggestion, I removed the hard drive and connected it to my desktop pc. Ran a virus scan, and it found several malware/trojan files on it. I dont know how, because I did format it before installing win7 on it.
Anyway, its done. It seems to be working just fine.
I greatly appreciate your help and advice and once again I apologise for the lack of info I initially presented.
Thank You, Thank You.