Pop-ups in safari 5.0

Hi,
A few days ago I disabled the pop-up blocker in safari in order to fill out a form. I then enabled it again, but for the last three days I have been receiving 2 pop-ups which appear at the exact same time, but randomly once throughout the day. They are from "skill2thrill.com" and require me to force safari to quit unless I click ok on their advert. Any recommendations, ideas or input will help.

Thanks,
Dan (doesn't want his new apple experience to be the same as his old windows one)

Welcome to Mac Forums.
I'm assuming this a sex site pop up or something of the like.... but I digress.
Try going to Safari in the menu bar>preferences>security>and tick the desired boxes.
Then, go to Safari in the menu bar, and reset Safari.

Thanks for the reply. I have all of the security settings enabled but accepting cookies is set to always. There is also a large list of cookies stored in the computer, shall I delete these?

Also, the pop-up isn't porn related. If i remember correctly it says that I can win something if I click on it. I'm pretty selective in the sites I visit and things I download, no fun on this macbook pro.

"I have all of the security settings enabled but accepting cookies is set to always."
I would definitely change that to either never or only sites I visit.
I'd reset Safari, and check every box
I regularly get rid of all my cookies in Firefox and Safari.
I don't believe cookies in general generate pop-ups, but do believe that pop-ups can be added to cookies, so, I still like to get rid of them.
There are some sites (esp porn) that pop ups come with, even if pop-ups are blocked in your browser settings.

A search found this interesting article, which LOL, brought up a little pop up at the beginning, so clear your cookies after reading
Pop-ups With Cookies

thanks for the help. I've done what you said and i'm now waiting to see if they come back. If they do.. is it possible that i have a "mac virus"?

There Are no Mac Viruses, so that's not a possibility.
As far as trojans, if you were to download and install certain software illegally, or Porn, P2P downloads, there is always a possibility, however, this would effect other windows users, and not your Mac.
See http://www.mac-forums.com/forums/switcher-hangout/23835-official-mac-antivirus-firewall-faq.html to get a bit more insight, better than I could ever explain.