Speed Cleaner is an application that is installed with other applications. It is considered by many users as doing more harm than good. In this case it is recommended to just uninstall the it and use another one that it is safe and gives you the possibility to analyze results. For instance, CCLeaner is a good application that gives you this possibility.
If you have trouble removing Speed Cleaner, use Revo Uninstaller. Even if it can't uninstall the application normally, it will force it to uninstall by wiping out all traces of its presence from the system.
After that, try running AdwCleaner to make sure that there are no leftover rogue registry keys or toolbars in your system.