I"m not showing any advertisements on my end. I tried three different browsers (IE, Firefox, and Chrome) and there are no ads. Maybe you have some sort of malware installed?
i had no malware, all scans came up clean, but i did a fresh install of Mozilla Firefox and now all is good.
I had the same problem a while ago and it was with random sited had ads they never had before. also did a fresh install and problem solved