firefox tweaking out please help.?

[Fubar420]

Hello, Please bare with me, this is a big problem, anyway, I'm Having a problem with Mozilla Firefox. It started about a week or so ago, every time i open firefox and try to do go to a website, everythings fine, but within a minute all of a sudden im being bombarded with new tabs and a few new windows of random things. (Mostly the new tabs). Anyway like one of the new tabs says: "You Are currently browsing the web with firefox and your video player might be outdated." And then there is a white box that pops up on top of that same page that says: "You are currently browsing the web with Firefox and it is recommended that you update your video player to the fastest version available.
Please update to continue"

The next tab takes me to a page that says: "Install video downloader to watch videos. (Recommended)"

Heres The Really Annoying part, Theres Several new tabs that say: Download PC Performer, Then a few that say download Codec Performer.
Also theres a couple tabs for lightspark player pro that i guess it says im supposed to download.

Finally the rest of the tabs are basically advertisments for random things, then a bunch of duplicates of the ones i mentioned earlier. To the point where the browser is so slowed down i can barely do anything, the only reason i can do this is because i opened a new window and all the tabs are on the other window, and they just keep coming and coming. Actually AVG just popped up a message saying something about Mozilla Firefox is using alot of memory, and it said 1Gig.

So Whats going on here? do i have a virus? I've never seen this before and it is very very annoying and concerning.

And one more thing, about all the new windows that keep opening up, just about every other time i click on something (Like when i clicked on answers to get to yahoo answers) a new window pops up either advertising a game like wizards 101, or progressive insurance, or learning a new language. and sometimes they just pop up every few minutes. When i click on firefox and go to options it says pop ups are disabled, I dont understand whats going on, If anybody can help PLEASE DO.

PS: Something just popped up and it says ad-ons may be causing problems, the following ad-ons are known to cause stability or security problems: Scorpion Saver 5.0. So I am Going to disable it, Could this be causing the problem?