Window Minimizes

I use Windows 7. For the past few days whenever I watch a video/Movie in Full Screen Mode in Google Chrome and use Silverlight in NetFlix, automatically minimizes back to the original size. I also play Sims1 and it affects game play. The game goes down to task bar, not crashing.
It's very frustrating when your trying to watch a movie or play and the full screen doesn't stay the way I want, please help me resolve this issue.
I use AVG AntiVirus, I don't know if this is the cause. I have set it to Game Mode.

 

Anyone? Can someone help me please?

 

Wild thought but is there something stuck under your escape key? Stray crumbs under keys can cause them to activate either randomly or continually.

 

Thank you for answering Chookers. I bought and installed a new keyboard and mouse. That didn't do it.

 

Well, it proves it isn't those, at least.

I can't help any further, I'm sorry. I don't use any of the things you mentioned. I have used AVG in the past but I switched to Avast ages back and I'm out of touch with AVG.

Someone else?

 

NadaWildflowers...

Do you or did you at some point have MS Office? I found this, and apparently, a component of OneNote was causing the problem:

http://www.tomshardware.com/forum/115032-13-random-game-minimize

You might take a really close look at your autoruns to see if one of those is causing your problem. Type msconfig in the run/search box and press enter. Check the startups tab to see if one of the items there could be causing the problem.

To get a closer look at your autoruns, you could try the program Autoruns:

http://www.majorgeeks.com/files/details/microsoft_autoruns.html

Could be something else like something to do with dual monitors if you have more than one, or it could be a driver clash. Autoruns is where I would start...