Shamu,
I know you tried Malwarebytes, but it is not the compete package. It is for malware. I would also suggest you go here:
http://www.kaspersky.com/virusscanner
I know you have to register to use the virus removal tool, but it is free, and if you uncheck the send me emails they won't bother you. It is over 100 meg, but it is top notch and very complete. I would try that before you do much else. With both machines acting weird seems like a virus you got on both machines. Hey its free, and I'm an idiot!
Once you download and run the scanner it will ask you if you are finished, click yes and then remove the downloaded file and it you won't have it on your machine anymore.