If there are too many jQuery-s loading in your website, that will make an error in one of the Joomla's core files. You should install jQuery Easy, because it is getting out all jQuery loading from the website, and loads only that one, which you pick. You can set it up in your Extensions → Plugin Manager → System – jQuery Easy → Basic Site Options. You can specify a jQuery version, or pick Joomla! framework, which works most of the time.
We don't need jQuery UI, but some extensions do, so you should pick one there too.