Windows 7: Help locating possible trojan or other virus

So my saga with possible viruses continues...while playing a game with a friend just a few minutes ago, my computer took on a mind of its own and began opening strange command prompts as if they were cd'ing to the locations of other games, as well as moving the mouse around, opening windows, etc. My immediate reaction was close everything not necessary (i.e. the skype call, the game, itunes, etc), open task manager, search it, and unplug the internet connection, to see if I couldn't catch something in the act. However, I found nothing.

Possible viruses always confuse me, because I am usually careful about what I download, where I visit and what I give access to, and the only programs I have installed recently have come from sites or developers I trust. Once again I ran scans, malware bytes and MSE, I found nothing. I found nothing extraordinary running, no odd tasks in the task scheduler, no strange programs installed, everything seems perfectly fine. And yet my computer behaved as though there was a second entity controlling it, be it a remove access or automated program, or some weird-ass glitch bug thing that made windows do random things (yeah right...). Everything which occurred could perhaps have happened if my mouse/keyboard drivers had a fit, its not like the mouse movements seemed to have a purpose, and everything which opened I have on my taskbar or in other easy to reach places which were displayed at the time.



Does anyone know what this may have been, where it may be lurking, or what I could do?

Thanks,
Tom

You could try a scan with WDO.

Use a USB flash drive if you have one that you don't mind formatting.

Tomha, are you still running without a firewall?

No actually, I haven't been running servers lately so I turned it on a couple of days ago.

What method did you use to play the games with your friends.
1. Was this game streaming?
2. Were you at a LAN party hooked to other computers?
3. Was these games on your computer already or did a friend bring a DVD with the game on it.
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I hope you get the idea. Remember a infection can come from any door left open. A friends DVD or USB memory stick, utorrant download, P2P, a LAN hoke up with another computer just some examples how infection can get in your computer. Of course which website was used for the download and if they used a special down loader program. Your scans with MSE and MAM is a good start.

I also like Windows Defender Off Line like UsernameIssues posted.

Another suggestion would be Eset online scan.
Free Online Virus Scanner | ESET