What do I do after I have been using CCleaner?

Who told you it messes with the registry? CCleaner is one of the safest windows junk cleaners available and its performance can be increased by using Shane Gowland's CCEnhancer. The registry cleaner included is one of the safest registry cleaners you can use it removes registry keys left behind by uninstalled software. A lot of people will tell you to avoid all registry cleaners and you could argue about it all day, I personally do use registry cleaners and registry defragers. There is absolutly nothing wrong with CCleaner.

Its better if you reinstall windows if you want a fast clean machine to do that follow this http://windows.microsoft.com/en-us/windows/help/install-reinstall-uninstall

Also I doubt that CC Cleaner will ''Damage'' the machine that bad. If it isn't broke don't fix it.

Not a thing wrong with CCLeaner in my opinion. I've used and seen it used on over 100 computers without issue.

Maybe you should install a virtual drive and run your normal daily processes (browsing etc) through that and keep your computer for the gaming. That way, when you've finished your internet activities, you can shut down the virtual session and still have a clean computer.

Also you should try to avoid always reinstalling your OS every time you want a clean machine like @Blake Emery suggested, as it can clean to hard drive failure.

Just so you understand: CCleaner is ill-advised because it deals with registry. There is more risk than gain when you edit and delete entries from the registry. Its not logical to touch the registry unless you are fixing specific problems related to said registry. Leave it alone, its not slowing down your machine. The part of CCleaner that does some good is the removal of all kinds of "junkware" and "bit-rot" otherwise known as any piece of data that is left over from your browser, history, etc. CCleaner has a wide range of options and types of files it deletes. In addition, you can specify it to delete application specifics even outside the browser.

Use CCleaner if you wish, just stay away from the registry portion. Also, understand what you are deleting before doing so!

Personally i do not use any registry cleaners I found that they did not effect the speed of my computer at all and i do not like messing with the registry, the extra keys will not slow down your computer to the extent that you will notice it. If my computer is starting to get a bit slow i tend to just backup, wipe the drive and start again which do about every year or so

On a more extreme note, infected registry keys mean NOTHING if you removed the active files.

i used to use CCleaner on my machine all the time, my system never slowed down or "screwed" up like you seem to think it does. i also recommend it to all my clients who have never complained about their system "screwing up". don't knock software until you have tried it.

I know for a fact it does mess up some programs I work for a computer software company and we constantly have customers calling after they run this and they start getting errors in out program and we have to reinstall it. I have been recommending customer to stay away from running it as it only causes more problems it seems.