None, really. None of those will do anything that you wouldn't already be able to do; they are just easier because they don't require any knowledge or effort to use and the process is automated. However, this also increases the chances of screwing something up. Besides, most of the time there is no need to mess with your registry and you don't need third party software to delete temporary files. Furthermore, those programs won't do the things that actually may improve performance, such as tweaking your startup programs/services and uninstalling unneeded applications.
Most of the time a slow system is due to either malware or just a ton of useless crap that's consuming system resources - these effects will be more pronounced on a low performance machine. That's why people so often notice a large performance boost (in reality just getting back previous levels of performance) after wiping everything and re-installing the OS.