Searching for the Best Registry Cleaners Online

We have a family desk top computer. The kids use it to play games and things like that. However, I think they may have clicked on something that they should not have because now the computer is not working properly. I have been searching for the best registry cleaners online. I am pretty sure that there is something wrong with the registry but I do not know enough about computers to fix it myself. I am hoping that I can find something online that I can download and have it fix the computer quickly so that we can get it back up and running again soon.