You could use piriform free products for safe cleaning. It will not clean the system files required for easy and effective functioning. Ccleaner, speccy computer information ,recuva recovery program and defragger. These are really marvellous free programs. Ccleaner, when you use, you could also add custom folder to clean, like windows\temp.
For any program, pl visit the authors site or majorgeek.com. You could later update it by program updates features. Do not download from suspicious sites, which contains unwanted bundled programs
In all in one repair tools select the item for which you want to trouble shoot. It works and saves time.
Another suggestion, download panda usb vaccine, which will prevent autorun.inf from pendrives to computer and vice versa. Your computer is safe from pendrive attacks