Hard drive light stays on and computer freezes randomly in windows 7

I am little bit worried about my harddrive. Previously I had 80 gb harddrive and then I upgraded it to 320 gb. I have dell latitude d630 laptop with two operating system. Windows 7 and XP. When I use Windows 7 then my computer specially hard drive light stays on and mouse is busy and I have to restart my laptop however in my XP this problem is never seen. I also installed vista and deep formatted the hard drive but the problem still persists in windows 7. The system is normal but when I surf internet via mozilla or chrome. This problem arises. I have done everytrouble shooting I can chkdsk and everything but when I use chkdsk in my western digital harddrive, it says error. I am thinking its harddrive issue what do u say?

thanks

OS is Win 7 Prof

Run the western digital diagnostic tool, if it says its bad, then time to rma the disk.

It's a good sign of some naughty activity running in the background. Run your AV and any/all malware and spyware software you have.

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