A frustrating BSOD screen, please help.

OK so, as I was on my computer (which was about 8 hours ago), it randomly made this beep noise and following that, my computer restarted by itself. After the restart, my programs would, either not run or would experience difficulties running. And so I thought it was an OS problem (mind you, I came to this conclusion after long hours of testing). And so as I was merrily trying to install xp again, the BSOD bombed on me (this had happened before when I was experiencing restarting and program problems and so thats why I had jumped to the OS conclusion, it's my fault, as I should have done more research). The error message read:

stop: 0x0000007B (0xF7BBE524,0xC0000034,0x00000000,0x00000000)

I just need some sort of help as to why I'm experiencing this problem. My computer configurations are:

Emachines (I know, WHY did i buy it)
3.06 ghz
533 Mhz FSB
512 mb DDR SDRAM

I would really appreciate it, if I could could get ANY feedback (I wouldn't mind for a solution, but at this point *after 8 LONG hours*, anything is appreciated)

THANK YOU!

From auhma.org --0x0000007B: INACCESSIBLE_BOOT_DEVICE

Windows lost access to the system partition or boot volume during the startup process. Typical causes: Installing incorrect device drivers when installing or upgrading storage adapter hardware, or a virus.