Need help right now

[Bahamut2000X]

Well I was just cruising online today when a pop up came up (getting through my pop up stopper by the way) Well I closed it and didn't think much of it. Until I try and get online later today and suddenly my homepage is changed to the pop up's homepage, my CD-Rom drive opens up and more pop up's open up. Not to mention my computer has been a bit more messed up today afetr that pop up then it usually is.

I just ran a virus check and no viruses on my computer so I think I might have spyware or something. If anyone knows how to get rid of this it would be much appreciated.

EDIT: Ok well just thought I should mention this is startign to get even worse as the number of pop ups are becoming more frequent and now some won't even close until I do what it tells me to do. (Which of course I won't) So ya if anyone could give me help on ridding my self of this right now, it would be much appreciated.