Program windows turn gray and then go back to normal again

I installed Ubuntu 14.04 on a Toshiba C50D-A-133 laptop. After installation I opened a terminal, and ran sudo apt-get install with some packages. I remember PlayOnLinux , GIMP, etc.

While the packages were being installed I started Empathy to enter the access data from my jabber account. In the shell window I saw that the Windows fonts were unpacking. Empathy fades to gray, and after 1 or 2 seconds it goes back to normal, and I could enter the jabber account information. At the shell windows apt-get was unpacking the next packages. Then after this a window with an update notification appears. I chose there preferences, and I unmarked the checkboxes there. After closing, the windows turned gray too for about 1 or 2 seconds, then the notification "no updates needed" appears.

I think that the windows became unresponsive because the system was busy. Is this correct or could something be damaged or wrong with my system? No program crashed or was aborted, only turned gray for a second, and then ran normally.

The Toshiba C50D-A-133 laptop has an AMD E1-210 which only runs at 1GHz, not that great by modern standards. It is normal with a laptop with a slow CPU like that for the Ubuntu Software Center window to dim to gray when there are multiple packages queued up waiting to be installed. An application window turns gray when the processor is busy and the application is waiting for the processor to respond, and then after some time has elapsed, it times out and the window dims. A gray window caused by a timeout that dims and then goes back to normal won't cause any damage to your system.

There is something that you can do about it. If you find the gray-looking window in the Ubuntu software Center annoying, you can install multiple packages from the terminal using a single command of the form:

sudo apt-get install first-package second-package other-packages  

...where you substitute the package names of the packages in the command with a space between each package name. If you install packages from the terminal, the terminal window will never turn gray and you will not have any problem with the window freezing, forcing you to force quit the Ubuntu Software Center and then try to install some packages that were at the end of the queue again. This is sometimes necessary, because when you force quit the Ubuntu Software Center the Ubuntu Software Center sometimes removes packages that have not started being installed from the queue, so you have to search for those packages and click the Install button to install them a second time.

Once you get past the obstacle of updating your system and installing packages, you should expect to have fewer problems with applications windows dimming to a gray screen or not responding. On a laptop with a slow processor like yours, you may find it necessary when using GIMP to save your image in the middle of the job, close GIMP and then reopen the saved image in GIMP and continue the image editing from where you left off. Another tip for preventing application windows from getting gray screens is to avoid multitasking other applications when running a processor-intensive task.

This may have more to do with available RAM than with CPU. I get this problem frequently in virtual machines which have lots of CPU (I may not be running much of anything else) but sharply constrained RAM allotment. I agree with the prior observations, however, that multitasking a lot of processes at once, especially when one or more of them requires a lot of resources, is the main trigger of this grey-out behavior. It will cause a lot of virtual memory swapping. (That said, if you have a slow CPU that might also cause this problem, even if low RAM does, as well.)