well I got two problems

1- My hard drive begins to make weird noises. While it does this, the whole system freezes and crashes, including the keyboard and mouse. The noise resembles the same swishy noise a CD drive makes while trying to read a bad CD.
I have to restart the whole thing.

2- Yesterday my hard drive just failed and died in the middle of something, it didnt even make a weird noise, it just shut off and restarted the whole system.
Because of that, system files were damaged. Fortunatelly, I managed to fix that with the recovery console. Unfortunatelly, I think other files were damaged and are undetectable by registry fixers and anti virus programs. My videos and DVDs dont work!!
The weirdest thing is that all sound works, all 3d applications work, but everytime I try to watch a video clip or a DVD, it crashes and restarts the whole thing instantly.
Something to do with the codecs? Damaged hard drive?

Please help ???

The first thing you need to do is scan your HDD for defects. We'll need to know your HDD manufacturer in order to recommend a utility for this task.

It's actually pretty difficult to provide any good help if you don't tell us about the hardware you're actually having a problem with. Please read this.

Well the Hard drive specification are these:
Maxtor 6E040L0 40Gb. 7200rpm Physical Buffer Size 2048Kb
Ultra IDE obviously.

My computer is this:
P4 2.8 Ghz Socket 478 533mhz Bus 512 L2 Cache
1024 RAM
ATI Radeon 9550 256 MB
Windows XP Pro

I think that is all.
thanx

The Maxtor diagnostic utility is PowerMax. Instructions are available on this webpage. Once you've established if there are any defects, post back.

If there are any defects, the next most important step is to mark any bad sectors in the file system and attempt to recover any damaged files. Do this by running the command prompt (Click Start, Run and type cmd) and use the the following command: chkdsk c: /r

You will be informed that the drive cannot be locked and asked if you wish to do this next startup. Choose yes, then reboot the system. This will take a while, possibly up to an hour depending on the state of the disk, but it's very important step to try and prevent data degradation and preparation to ensure any necessary backup attempts will be without error.