Sounds like a pretty simple case of your video card failed. If it's under warranty, get the manufacturer to replace it, otherwise that cost is on you.
Also, just FYI, defragmenting and CCleaner have no real diagnostic function. Defragmenting just gathers up the various little chunks of files scattered about the physical surface of the drive and puts them in a contiguous block. Once upon a time this could improve overall system performance a reasonable bit, but these days it's all but useless for the average user. Particularly with "cloud" services being rather popular.
CCleaner, by and large, just provides a central location for tools already built into Windows. It also contains a registry "cleaner" which will be more likely to cause problems than fix them. Once upon a time, CCleaner was a very specialized tool for the IT professional type. Then it was "discovered" by a few people who want to show off and repeat a bunch of half-understood and badly mangled advice someone else gave them for a completely different situation. The result of which is CCleaner sold out and is now actively trying to market itself as a kind of panacea tool, where it's primary utility to people is providing a single button to do things like empty the recycle bin, delete Internet Explorere's cache files, and things of that nature... All of which already have methods for doing so in a stock Windows environment, it just requires a little more effort.
My computer used to be able to play several games such as Far Cry 3, Civ5 and Hitman:A
Then (because of reasons unknown) I had to plug in an outer graphics driver (The type that uses an USB).
After I removed the outer graphics driver I noticed:
-Windows AERO didn't work
-"Desktop windows manager had stopped working and was closed".
-Some games would not start (without sending an error message)
I tried several different things to fix the desktop manager problem such as:
-Restarting it from "Services.msc"
-Reinstalling the games
-updating my drivers
Is the "desktop windows manager" error the reason why I can't play some games?
And how can I fix it?