Checksum Error when Vista Boots

Hello all. I am in great need of assistance.

When I got to my desk this morning, my laptop had on the screen "File is possibly corrupt. Its header checksum does not match the computed checksum." Nothing had changed, and when I left the office the previous evening everything was fine.

I have a HP Pavilion DV8000 running Windows Vista Ultimate.

I powered down the PC and powered back up and same result. It doesn't even get to the windows loading screen.

I then placed my Vista CD in the drive and attempted to boot from CD. It loads all the files and then I get a screen that basically says the following:

Windows failed to start. A recent hardware or software change  might be the cause. To fix the problem:
1. Insert your Windows installation disk and restart your computer
2. Choose your languate settings and then click "Next."
3. Click "Repair your Computer"

File:\Windows\System32\boot\winload.exe
Status: 0xc000221
Info: The file is possibly corrupt. Its header chechsum does not match the computed checksum.


I then hit Enter and it asks me to choose an operating system to start and the only option available is "Windows Setup [EMS Enabled]"
If I choose that, it takes me back to the previous screen.

I have also tried the Windows Memory Diagnostic and it says "Hardware Problems were detected."

What hardware problems? What is my next step to determine what the hardware problems are? This notebook is only 1 1/2 years old. Help!