Programs Shutting Down Almost Immediately?

A few days (probably about 3) ago, I installed StarStaX. I'm a photographer, and I also have Lightroom and Photoshop Cs5 installed on my computer. Early in the day, it was totally fine, but then, my mouse gave out. It's a real piece of junk that you had to plug in and unplug to get working every time you'd restart the computer, (but it was USB, so no worries). Fortunately, I have a Wacom Tablet that I could use instead. However, when shortly after I started using the tablet, as soon as I opened StarStaX it would shut down saying the program had stopped working, even though it had been fine that morning. I tried opening it back up several times but the same thing happened. So I tried the old mouse again, which still wasn't working. An error message stating that an "unknown USB device" was connected to the computer started showing up for the first time. Anyways, to get StarStaX to load, I had to shut down Photoshop (and possibly Lightroom) and even then it was still iffy. Not long after, once I was done stacking photos, Lightroom began displaying the same shutdown message, most often if I went to change the color temperature of photo (so just a slider) or if I went to edit in Photoshop. Previously, these programs had run very quickly, even with several other programs like iTunes or Photomatix running. Now even Photoshop usually has to be the only one running or it will end immediately. So, I installed CCleaner, (I have no internet on the described computer so I had to carry it over via a Flash Drive), and deleted a lot of junk. I also took off some programs I know for sure I wouldn't use. When it still wasn't working, I ran Error Check on the C Drive (I think that's how you say it), and it still will not work. After this, on the advice of another user, I downloaded a program called Advanced SystemCare but that did not work.I am unsure as to what could be causing this problem, so sorry if it would be more appropriate elsewhere. It is not connected to the internet, so I don't think it's a virus, but I am unsure.Here's the specs on my computer according to SysInfo:

Tech Support Guy System Info Utility version 1.0.0.2
OS Version: Microsoft Windows 7 Home Premium, Service Pack 1, 64 bit
Processor: AMD Phenom(tm) II X4 830 Processor, AMD64 Family 16 Model 4 Stepping 3
Processor Count: 4
RAM: 7927 Mb
Graphics Card: RS880, 256 Mb
Hard Drives: C: Total - 941622 MB, Free - 658375 MB; D: Total - 11955 MB, Free - 1449 MB;
Motherboard: FOXCONN, 2A92
Antivirus: None

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