memory

Okay my friend is having a little trouble. He has been getting BSOD's here lately so he asks me to look at it. The computer would make it to the desktop but it was froze. I couldn't do anything. The wallpaper would show up bot none of the icons. Well, I start running tests and got all kind of memory failures. He has 512mb(2x256mb) of ram so I took one of the sticks out before I started the tests. After the tests, it made it to the desktop and finally all the icons showed up but no wallpaper. He wanted me to try and find all of his music but could not. The folder where he stored it only showed like 6 or 7 songs. He has over a thousand. The whole time I was looking for his music, the hard drive light would never go off. It took foreve to do anything. Would that be because there is only 256mb of memory installed?

Would you think that one of the sticks failed? If so, why can't I find all of his songs?

Would this be a problem? He wants me to take the hard drive out of his pc and stick it in mine to see if I can find all the music. Since there is Windows XP installed, could I hook it up in mine as a second hard drive and read all the contents? What about unplugging the one in mine that has the Windows XP on it and hook his up in place of mine? Would that be a problem unplugging the one with the operating system on it? Which would be the better way to go, hook it up as a primary drive or a secondary drive?

His computer is a Dell 5100 and mine is a Dell 9100. They are both SATA drives. He thought maybe the hard drive failed because ever since he bought the computer, he could always here the hard drive running and the light would constantly flicker. But I don't think it is the hard drive because it still had all the files on there. I think it is the memory because of all the errors during the test. I probably received like 4 or 5 errors related to memory.

__________________
Thermaltake Armor Series VA8000BWS
Intel Q6600@3.3ghz
Tuniq Tower 120
Nvidia EVGA GeForce 8800GTS 512mb
OCZ 4gb's(2x2)
OCZ 700 Watt GameXstream
WD Caviar SE16 320gb
WD 250gb
Soundblaster X-Fi XtremeGamer
Windows Vista Home Premium 64bit