Have been using CCleaner for years, never had a problem with it. I use it periodically to clean the registry, and it seems to only delete invalid items. I also use it to uninstall hotfix installers which can take up many GB of space (once I am satisfied the HF didn't cause other issues). You need to select the option to do that.
Recently, I installed Driver
Cleaner Pro 2012 when I momentarily lost my head. Normally I check utilities out before I install them, but this one I just went ahead and installed. After the scan found 8000 problems, I was mighty suspicious. When I googled it, I found it was a fake registry cleaner which only "fixes" problems if you buy their full version software (problems it created on its own, of course). Fortunately, I hadn't yet clicked on the "Fix problems" button, which apparently makes nasty registry changes to basically lock you in for life.
Stick with CCleaner.