There are too many 'dubious' contents floating around Youtube.
Moderations shouldn't be so lenient.
Some shocking content only serves as click-enhancers, don't add anything to the content quality of the site and are very bad influence for minors.
YouTube.com contains a wide variety of interesting videos, marred slightly by technical delays that seem to be related to buffer memory and by the difficulty of contacting Google to complain about those delays. You can't always trust that URLs shown in videos refer to web sites that actually exist, but it can be a useful source of information nevertheless. (And of course, domain names are not always renewed, so a site may have existed when a video was uploaded, even if it doesn't exist anymore.)
Regarding child safety, I am thankful that YouTube allows people to post videos about sexual matters, although outright pornography is disallowed, as is graphic violence. People do seem to have the option of complaining about videos that violate their terms of service.
Dialogue regarding particular videos can be interesting, as long as one is prepared for the fact that people will not always agree with you. Some folks will call you insulting names or say insulting things about you. That's just the way the cookie crumbles, unfortunately (or fortunately, if you believe that a sign of maturity is the ability to live in a diverse world).
YouTube is a safe, popular video sharing website run by Google. It has some very interesting stuff. Unfortunately, you might accidentally come across some pornographic/inappropriate content, or a fake software serial key/crack video which links to malware or phishing websites, so be careful.