Xbox 360 disk drive

My 360 always seemed to make loud noises when booting up a disk and sometimes even during game play ,but lately some of my games aren't even working and I get the "unplayable disk" message. I decided to get a 360 opening kit on eBay and follow a few youtube vids on how to fix it. Some say it's a magnet issue and I really hope it is because that would be an easy fix , but I can't help feeling there is another problem.  My question is has anyone tried opening their 360 and fixing a similar issue and if so were you successful? Thanks in advance.

P.S. I have tried the postcard trick-http://www.youtube.com/watch?v=xo2c2x8idjc

My question is, do you still have a warranty?

Careful...I read on GS someone did the card trick and messed it up enough to void his warranty.

Were your disks getting scuffed by your 360? That happens to me with GTAIV and Mass Effect. It's not an actual scratch, but small white scuffs that can be wiped off with some effort. If that's the cause of your unplayable disk message I would recommend not messing with the magnet.

I still have my warranty intact. I don't see how someone could have voided their warranty with the card trick unless he did it completely wrong. My disks aren't scuffed at all. The fact that I can hear the disk start and stop moving is whats troubling me (also why I think it's the magnet problem).
-Thanks for the feedback +)