I would imagine that to uninstall the older version you should use the uninstaller that is in the older version folder. I would make sure you have tranfered all your setting over first.
CC 2014 uses NEW plugins https://forums.adobe.com/thread/1499663
-so do not uninstall the older CC programs if you use plugins in your programs
http://helpx.adobe.com/creative-cloud/help/install-apps.html to install or uninstall
Be sure you have everything like plugins in the new PS CC 2014, seems a lot of things are not compatible. See the discussions here: Re: Why is everything new apps in 2014 update?
Well, that wasted an hour of my time figuring out why I now have two versions of PhotoShop. Shame Adobe didn't explain this in the CC interface, shame Adobe are doing it this way too.