DAMN i hate those I had to go get some cracked avs for my friend. he had almost the same problem. He didnt have an av and he went and downloaded what he thought was a free video game demo but it wasnt..... He started running realy slow then his backround changed and said get norton free click here!!!! and stuff like free full games here!!!! and random IE windows would pop up to a site saying clean your registry now!!!!!!!!!! or some bull shit. so he disconnected from the internet. then every 5 hours (gradualy geting shorter and shorter) His system would reboot. So he unplugged his pc and i went on my pc to get kaspersky for him (using secret ways he he) and i burned it to a cd. Went to his house and installed it (took a long time) then his pc went back to normal after catching a trojan and a worm.......
-Go here
-Download
-Run
-Look at any processes running in perculiar places, or ones you don't know about. Remember the location, reboot in safe mode, delete.
Wow this happened to my friend once. Your going to have to Re-install your OS. lol they infect your computer then annoy you to try to make you dl their software to remove it.