Computer crashing fairly often

Okay so my computer seems to be crashing a lot. I leave it on most of the time, since I'm running a media-server down to my PS3 downstairs. Sometimes when I return to my PC, it will be in sleep mode, but I will not be able to get it out of sleep mode, and will have to turn the PC off to get it back on. Other times, it has crashed before reaching sleep mode, and there is simply a black screen with an MS-DOS style cursor, but not text. Again, the computer is unresponsive and needs to be restarted. This used to happen around 5-10% of the times I'd return to my computer, but lately it has increased vastly and now is around 75%.

Nearly every time I use uTorrent, the computer seems to crash in this manner. Similarly, I can often predict it is going to crash when Google Chrome becomes slightly unresponsive. Reading around, similar crashes seem to happen to other people when hard drives go bad, and for some reason I think it is more of a hard drive problem than a software problem.

I'm in Windows 7 64-bit.

Any help that could be given would be appreciated, and just ask if you need to know anything else.
 
With computers that are running nearly all the time, it is important to keep them clean inside... You can run chkdsk (check disk) on the C hard drive and use Memtest86 to check the memory
 
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