I did, and that didn't help solve my problem at all. But I posted this question somewhere else, and someone suggested that I disable/uninstall my extensions and addons one by one until I perhaps found the problem, and so I did, and it solved my problem! The problem was I had this extension called Download Embedded 0.5 from this link:
CODE
https://addons.mozilla.org/en-US/firefox/addon/1993
It has a bug or glitch that causes firefox to crash when going to youtube, and also I looked at the reviews, and some users are saying that when using media players it crashes when doing that also. If you have it please uninstall it, and use some of the other ones I use, such as: DownloadHelper, Fast Video Download, or Magic's Video Downloader. Thanks, and please uninstall it!