mohadry

i just got this computer yesterday as a present from my father, but for some reason it didn't have an anti-virus so no big deal i downloaded avast home edition but whenever i try to install it the installation screen fades away and it's like it's not even opened, i tried to install avg, kaspersky any thing but still nothing, tried using online scanners, but they don't get loaded even though i can load any other site. i also tried downloading malwarebytes and using it.
it found a few things and said it removed them but it didn't solve my problem.
also whenever my pc is on for a while IE pops up and opens a weird page hxxp://jj.gxgxy.net/html/qb2.html
i googled it and some people said that it was some sort of an autorun so, i downloaded autorun eater and used it but it still didn't solve the problem.
others said that perlovga removal tool is the one for it but it still didn't solve it.
i don't know what else to do, can any one please help me...